Authentication failed. How to fix authentication error when connecting to WiFi

Useful tips

WiFi Authentication Error on Android is a fairly common error where the message “Saved, WPA/WPA2 protected” appears. Unfortunately, not every user understands what it means and how to fix it. However, in order to solve it you need to know why it occurs. Therefore, first we should answer the question of what WiFi authentication is.

WiFi authentication error on Android phone or tablet - this is a security key check. This check necessary to increase the level of network security. The point is that point WiFi access has a fairly large range of action, thanks to which not only trusted persons, but also attackers can connect to it. Data encryption technology is used to prevent unauthorized connections. Therefore, to connect to the network we need to enter a password.

Why does the authentication error appear?

There are two reasons why WiFi authentication error may occur on Android devices when connected to the network:

Incorrectly entered key.
Data encryption type mismatch.

Now click on it and hold your finger until it appears extra menu, in which you need to select “Forget network”. Don't worry, it won't disappear. Only the data about her will be deleted.

Now start searching for available connections again. Try connecting to your router. Only this time, when entering your password, check the “Show password” box.

This will allow you to see the characters you type. Carefully check the correctness of the key. If the password is entered correctly, but the authentication error still appears WiFi networks on Android devices, you should go into the router settings and check the encryption type.

Setting the encryption type in the router settings

In order to enter the router settings, you need to connect to it. This can be done using a laptop or desktop computer, both via WiFi and cable. After connecting, open the browser and enter the IP access point in the address bar. As a rule, the device address is indicated on the case, in the instructions or in the box. In addition, you can view it in the network control panel.

To view connection information, click right click mouse on the tray icon (desktop area in the lower right corner). Select “Network and Sharing Center”.

In the central part of the window that opens, find “Connection type” and click on “Wireless” network connection" (or "Wireless Network" in Windows 8). In the window that opens, click the “Details” button. Find the line "Default Gateway IPv4". This is the address that needs to be entered in the browser.

Press enter and you will be taken to the login page. Here you need to specify your login and password. Enter admin, admin, respectively. Press enter. Now we are in the access point parameters. It is worth noting that the interface design may differ depending on the router model. However, the essence is the same for everyone.

Let's understand the main reasons for the message "Authentication failed when connecting to Wi-Fi" on Android tablets, phones and laptops running Windows 7.

Fixing WiFi authentication error:

The most popular reason. why the phone does not connect to Wi-Fi - the password was entered incorrectly when connecting to the router.
Make sure you enter the password correctly, taking into account capital letters and numbers,
the password may be just on English language!!!
If it doesn’t work, we’ll re-enter the password into the router. How to do this is below.

At the end of the answer, we will consider the option when the password is entered correctly but Wi-Fi does not connect. In this case, you need to reconfigure the network settings in the router.
This is interesting:

Connect to Wi-Fi on Android:

1. Click the "Settings" button on your tablet or phone - "Wireless Networks".
In the list of networks, find your connection that you cannot connect to and delete it.

2. Add the network a second time, carefully enter the password and try to connect.
If the problem remains - re-enter the password into the router and carefully enter it when connecting to a wireless network.

So, wifi authentication: what is it?

Authentication is a security check when connecting a device to Wi-Fi over a secure connection. During the authentication process, the device communicates to the Wi-Fi equipment secret code, entered by the user.

When correct specified password, The Wi-Fi router connects the device to the network, otherwise the connection is reset. Thus, only users who are part of the circle of “trusted persons” and who know can use Wi-Fi resources.

In other words, Wi-Fi authentication on an Android device is the message to the router of the code for entering the network and its subsequent verification to ensure it matches the password specified in the router settings.

Android wifi authentication error: what to do?

Typically the authentication process takes a few seconds. But sometimes when connecting to WiFi (after entering the password), the device shows the “authentication” status for much longer - a Wi-Fi authentication error occurs on the phone, or the device never ends up being authorized on the network.

Typically, this problem occurs for one of the following reasons:

1. The secret code for connecting to WiFI was entered incorrectly

If you entered the wrong secret code (you made a typo, entered it in the wrong layout, or simply someone changed the code without your knowledge), then you will not be able to connect, and the “authentication” status will last longer than usual and will end with an error message.

Solution: check that the password is entered correctly. If you are connecting to a wireless network outside of your home (for example, at your workplace), check with system administrator or colleagues new password.

If you establish a connection with, and are sure that the code was entered correctly, then we advise: perhaps they were changed without your knowledge.

2. Mismatch between the connection type in the tablet settings and the Wi-Fi equipment

Safety standards are constantly improving and changing, ensuring modern Wi-Fi equipment can operate in different modes that are incompatible with each other. And often a Wi-Fi authentication error on a tablet occurs due to a mismatch between the settings of the Android device and the network equipment.

For example, if Wi-Fi router is configured to, and on the tablet the access point type is set to WEP mode.

In this case, the tablet will see the network, but will not be able to complete the authentication process.

Solution: remove the access point from the list. Perform a search available Wi-Fi networks and try. If you have access to your router settings, you can also check the security settings and change them.

3. Large distance between router and tablet

In addition, the authentication problem when connecting to wifi may occur due to. In this case, you need to reduce the distance between the Wi-Fi equipment and the tablet.

Often, when connecting a computer, laptop or tablet to the Internet via Wi-Fi, the system displays an authentication error message. Let's look at what it is and for what reasons it occurs, and also give recommendations for eliminating them.

Authentication error: concept

The authentication procedure always involves verifying the authenticity of the user. Authentication involves entering a specific password. If the password is entered incorrectly, an authentication error is generated.

Authentication Error: Causes and Solutions

Having understood what an authentication error is, you should dwell on the reasons for its occurrence. As mentioned above, the error usually occurs due to an incorrectly entered password when connecting to a wireless network. You will need to make sure that you indicated it correctly - it was used desired layout and language. If after this you still cannot authenticate, this means that there has been a failure in the network settings and you need to delete it. You need to do the following:

Go to the menu of your router and select the “Settings” section.
In the list that opens, click on the “Wireless networks” item, opposite it click on the “Delete network” button.
Click on the “Refresh list of networks” item, after which the network you are using will be available again.
Restart your router.
Open the authentication window and enter the correct password.
After these steps, your computer will need to connect to Wi-Fi.

If during authentication the password is saved, but a message about WPA\WPA2 protection appears under the name of the network you are trying to connect to, then you need to change the settings of the router. This is done as follows:

Go to the router menu and select “Network mode”.
In the tab that opens, change the “Only” mode to “Auto” and save changes made.
Disable the wireless connection on the device and restart the router.
Check that the entered password for connecting the Wi-Fi network and its mode are correct.

If after this an authentication error still appears, then you need to change the operating modes of the router. Proceed as follows:

Go to the “Settings” tab in the main menu of the router.
From the list that opens, select the “Wireless Network” section.
In the window that loads, set the following command opposite the Mode option: 11bgn mixed.
Save the changes by clicking on the appropriate button.
Reboot your router and try to authenticate.

If the system gives an error again, then again go to the “Wireless connect” section and enter this command in it: 11bg mixed. When repeated error You will need to enter 11g only next to the Mode option. Be sure to save your changes and restart your router before authenticating again.

To avoid problems with authentication, use a password consisting of only numbers. Be sure to write it down. In this case, you will not need to go through the password recovery procedure or reset it later.

Pay attention to the security settings of the router. They often cause problems with authentication. It would be better if they looked like this:

Version: WPA-PSK
PSK Password - eight numbers/symbols
WPA/WPA2 - Personal (Recommended)

In this article, we will look at some of the most common examples of authentication errors when operating devices based on the Android operating system with WiFi networks. At first glance, there can be nothing complicated in this matter, because the interface of phones and tablets based on this OS is exceptionally friendly even to the most inexperienced users, but she can also surprise.

In addition, such an error is a fairly common occurrence and in order not to get into trouble, first you should familiarize yourself with the information presented below and, perhaps, the connection problem will be solved easily and unnoticed. First you need to understand what authentication is and WiFi technology generally. Understanding this will give you the opportunity without anyone’s help and extra costs resolve everyday issues related to this protocol.

Authentication. What is this and why?

Often, during authentication, instead of the treasured “Connected,” a message like “Saved, WPA/WPA2 protection,” or “Authentication problem” appears on your phone’s display.

What is she?

This is a special protection technology that does not allow access to your personal or work network uninvited users who would use your Internet channel and waste traffic. You will have to pay for it. And the large range of the WiFi access point makes it possible to connect to it not only for the people for whom it was created, but also for attackers. This means that in order to prevent such unauthorized connections, high-quality data encryption and authentication technology with a low probability of hacking and password guessing is required. This is why you most often need to enter a password to connect to the network. The authentication data encryption method that suits your requirements can be selected in the settings of the router or access point to which your device is connected. The most common authentication method today is WPA-PSK/WPA2.

There are two main options here:

In the first case, all subscribers enter the same key when connecting to the network; in the other, each user is given a personal access key, consisting mainly of numbers and letters of the Latin alphabet.
The second type of encryption is used mainly in companies with a high level of network security, where a certain number of users are connected and it is actually important secure checkout authenticity.

If we have connection problems, before taking any action, it is recommended to use a proven method, which in more than half of the cases solves all problems, including authentication errors - reboot the router.

Another of the most effective ways to solve an authentication error, since it can often be caused by damaged firmware of the router located at your home, is to update its firmware to latest version. It is strictly recommended to update it from the official website of the manufacturer. It is also advisable to have a saved copy of the file with the router configuration, and if you do not have it, then do not be lazy to make it on your computer so that you do not have to select its settings again. In addition, it is better to make sure that your network is not hidden, that is, just check in the settings whether the “Hidden SSID” checkbox is checked and whether the name of the wireless network is written network SSID in Latin.

Authentication error. Why does it occur?

In fact, there are only two main problems due to which your phone may not connect to the WiFi network. But do not forget that in addition to the errors indicated below, similar problems may be caused by a failure of the router itself or due to conflicts in network settings. This is a separate topic for discussion.

The selected encryption type does not match the one being used.
Error when entering key

Most problems with connecting to wireless networks are due to errors when entering the key. In such cases, it is recommended to double-check the password entered in the connection settings of your phone, and if this does not help, use a computer to go into the router settings, replacing the access key directly on it. It is worth remembering that the key can only consist of Latin letters. If this does not help, one of the methods below should definitely help.

To solve the problem, watch the video:

Troubleshooting authentication errors

Not every user can imagine what setting up a WiFi router using a computer looks like and how to fix any connection problems, not to mention the reasons for their occurrence. Therefore, another way to solve problems is described below, but on the router side and using a computer connected to it, and not a phone.

To check the settings, you need to go to the router settings. To do this, open any browser and enter address bar IP address 192.168.0.1 or 192.168.1.1. This depends on the model of router you are using. After this, enter your username and password in the window that appears. If you have not changed them, you can find the necessary login information on the router itself, or in the instructions.
Next, you should go to the wireless network mode settings and instead of “b/g/n”, which is most often the default, change to “b/g”, after which saving all the changes made.
If all previous manipulations did not produce any particular result, then it makes sense to change the encryption type when checking to WPA/WPA2, if a different method was chosen, or vice versa - simplify to WEP, which, although outdated, sometimes saves the situation if other methods turn out to be ineffective. After that, try connecting to the network again from your phone and re-enter your key to pass the verification.

Knowledge of the listed nuances will help you cope with the error that occurs on many devices, regardless of class and cost, when working with various wireless networks, as well as understand the very principle of setting up wireless routers and access points.

A fairly common phenomenon. At the same time, users cannot connect a tablet or smartphone to Wi-Fi, despite using the standard router settings and entering the password correctly, which is very difficult and interferes with normal operation mobile gadget. This problem is easy to solve if you have some knowledge. It is enough to change some settings so that the mobile device can be connected to the wireless network. Users often encounter a situation where a newly purchased tablet does not display available connections or is unable to establish a connection. At the same time, Internet access is necessary to set up a mobile gadget, install applications, updates, without which the device will not perform its functions. We recommend that you carefully change all parameters wireless connection to the network so as not to reset correctly installed settings router. Any rash action may lead to the need to reflash the router.

Solving authentication problems when connecting a tablet or smartphone to a Wi-Fi router

Authentication when connecting to a wireless connection is the identification of the device and its parameters. It is necessary for security purposes - only this way strangers will not be able to use your Internet connection. On the other hand, authentication “determines” how compatible the settings that are used for the wireless connection are.

Security is ensured through user input correct password. In this case, all router settings must be configured in such a way that the tablet or smartphone cannot accept the connection, which will open up the opportunity for its owner to use the Internet.

Authentication errors occur in three cases. The first involves entering the password incorrectly. Since it does not require changing any parameters, we recommend that you make sure that you entered the combination correctly. If the key is specified correctly, but the connection does not become active, then the reason lies in incorrect data encryption. Often, simply changing the data encryption type is enough to prevent authentication errors from occurring.

The third reason is the incorrect operation of the router itself. This problem often occurs on budget models, since the quality of the device, as is known, depends on the price. In addition, the signals large quantity budget routers who work for standard settings, may "overlap". This primarily causes the signal to be interrupted not during authentication, but during the process of using the connection. Often incorrect work router may occur due to the load on one device, technical faults provider, a large volume of downloaded this moment files to high speed. Sometimes power outages can cause authentication issues and the inability to connect to the Internet.

Error Wi-Fi authentication is very easy to identify. Users of Android mobile devices will see the message “Saved, WPA/WPA2 protection” or “Authentication error”. It is worth noting that most often this problem occurs on smartphones, and not on tablets. In any case, the task of each user is to configure the router in such a way that such errors do not occur. They cause great inconvenience, especially at times when there is an urgent need to use the Internet.

What should the user do before making changes to the parameters? First of all, we recommend making sure that you are using the correct network name and entering the password correctly. If everything is correct, but the connection is inactive, try rebooting the router by turning it off and then back on. Many devices have a reset button. We do not recommend using Reset, as this will require you to completely configure the router.

Changing the connection subfrequency

There are a total of 14 connection subfrequencies. Moreover, the fourteenth subfrequency is used for military purposes. IN Russian Federation, Ukraine is allowed to use 13 subfrequencies for wide use. Often, routers from the same manufacturer select a specific channel by default. We recommend checking this setting and setting it to a new value.

To do this, open your browser and enter the numbers “192.168.0.1”. After that press Enter. Next, you will need to enter your username and password to access the router’s web client. Such information is contained in the instructions for the device. After this, you will be able to see the router settings. You should go to the Wireless tab. On the tab you will be able to see the Channel option. To make it easier to use the wireless network on smartphones and tablets, you need to set the Auto setting. It will allow you to automatically select a channel depending on the load on a particular channel. Do not forget to reboot the router after changing the parameter.

It should be noted that this change will help solve the authentication problem if mobile devices find many connections to the wireless network. This situation is common in offices and apartment buildings.

The password and network name are great importance when connected to Wi-Fi on tablets and smartphones. The network name must not contain the following characters: \, |, /, $, &, :, %. We also do not recommend using hyphens and dashes. As for the password, it is desirable that it consists entirely of numbers. Alphabetic characters are allowed in combinations, but many users who have encountered problems with device authentication recommend using numeric combinations.

To change the network name and password, you will again need access to the router's web client. After that, go to the Wireless tab again, find the SSID1 parameter and change it. Changing the password is also easy. You must first activate the Wireless tab, and then go to Wireless Security. Password PSK - this is the key that must be entered when connecting to wireless internet. After making the change, you need to reboot the router.

Encryption type

We recommend that you perform this setup simultaneously with changing the connection name and password. The optimal and reliable connection today is WPA-PSK/WPA2-PSK. This setting should be set in the Wireless Security section.

After this, you need to check the Version parameter. It is advisable to have the Auto version of the security standard installed. This may solve the problem on older devices that simply cannot work with the WPA2-PSK standard. Sometimes on new devices the firmware version is operating system does not support WPA2-PSK. The encryption type allows the device to use both WPA-PSK and WPA2-PSK2. It is supported by all modern mobile gadgets and represents more advanced settings than WPA2-PSK.

Tablet firmware and root access

An authentication error when connecting to Wi-Fi can often occur if there are problems with the firmware version of the tablet or smartphone. This especially applies to those whose users have made changes to the . In some cases, users are unable to connect to a wireless network if the operating system version is not authentic.

Any firmware contains drivers that are responsible for the module wireless communication. An inauthentic version of the operating system, accordingly, may use inappropriate drivers that prevent normal connection. In such cases, we recommend to fix the authentication error. Choose only high-quality firmware. First read reviews from people who have already installed software to your gadget. But this solution is suitable only for those who are convinced that there are no other options to fix the problem.

Authentication errors when connecting a tablet or smartphone to Wi-Fi are not uncommon. In this case, the solution to the problem is to change the settings of the router, check that the password is entered correctly, or change the firmware. In any case, when such situations arise, the easiest option is to reboot the router and double-check the combination entered when connecting. Before changing the data encryption type and other parameters, you need to make sure that this will not cause other failures in the router.

Probably the most common mistake that everyone has encountered at least once when using devices on Android based. Authentication errors appear when you want to connect your device to a Wi-Fi network.

So, let's try to correct the situation by understanding the reasons for the appearance of such errors. Accordingly, they need to be eliminated as soon as possible. Take your smartphone or tablet in your hands to follow my advice and instructions.

What is the reason for this error to appear on Android?

Did you take your device? Great, then let's try connecting it to the Wi-Fi network. After entering the password, you see the connection status “Authentication”. Then an Authentication Error pops up.

The error is saved as a message of the same name or as Saved, WPA/WPA2 protection, but there is still no access to the network.

This error will appear constantly, despite the fact that you disconnect and reconnect the network, and this can happen at home, when, for example, at work everything is working properly.

This message most often occurs if you entered the password for the router incorrectly, but it can also appear due to bad settings security on your router or phone.

Methods for solving the problem

Well let's start fixing it this error so that she no longer becomes an eyesore for you.

Well, that's where my advice ends. The main thing to remember is that proper configuration of your router is the key to the success of the performance of your devices.

Possibilities modern phones go far beyond voice communication. With no less success, they can be used to store and edit files and, of course, to connect to global network. Because the mobile standards are most often limited by providers; to connect to the Internet, owners of gadgets based on Android and iOS most often use Wi-Fi technology. But the mere presence of a Wi-Fi module in a mobile device does not guarantee a connection to the network.

It happens that the phone does not connect to Wi-Fi, displaying errors or notifying the user that the connection is impossible. Most often this occurs due to a failure or incorrect settings the device itself, but can lead to the same results incorrect configuration router modification system files, installation of custom firmware, non-compliance with communication standards, virus infection and, in rare cases, failure Wi-Fi module. So, let's try to look in more detail at why the phone doesn't connect to Wi-Fi and how it can be fixed.

Incorrect password entry, temporary failure

This error usually occurs when the Wi-Fi network cannot recognize the device connected to it. The reason is most often trivial - the user makes a mistake when entering the password and, as a result, receives a corresponding message.

Check that the password you entered is correct and try to connect again. Also pay attention to the name of the network. The Wi-Fi module on your phone detects not only your network, but also other access points, which may have similar names, for example, mydoms and mydons. Make sure you are connecting to your network and not your neighbor's.

If up to this point there have been no problems with authentication, first try rebooting your smartphone and the router itself; perhaps there was some kind of temporary glitch. Is your phone still unable to connect to your Wi-Fi network? Delete in WLAN settings saved network and try to reconnect.

The example discussed above is the simplest, but more often everything is a little more complicated, being associated with incorrect settings the router itself.

Router settings

You connect to the network, but the phone does not connect to Wi-Fi, it says saved WPA2 or WPA. After a few seconds, the “Authentication Error” message appears. If the password is correct, there is most likely something wrong with the router's security settings. It may also be that the phone says “Saved,” but the connection is still not established. It’s easy to get into the router settings; you just need to go to the internal address in the browser 192.168.0.1 or 192.168.1.1 . It is more difficult to understand its interface, since different models routers, it can differ significantly.

By default, the login and password are used to log in admin/admin(look at the bottom of the case). Before making any changes to your router settings, remove the network from your phone or at least, disconnect. It is also advisable to create a backup copy of your router settings - if you suddenly get confused or do something wrong, you can always restore. After making changes to the router settings, it also requires a reboot.

Region

Now a little more about setting up an access point. First, try changing the region.

In the settings this option is located in the section Wi-Fi - Advanced Settings, c – on the “Wireless” tab. In other models it may be located in a different location. In short, you need to first study the interface of your router. In the regional settings, the country in which you live should be selected, although this is not critical. Save your settings and reconnect.

Network mode

Much more important setting, which may prevent the gadget from connecting to Wi-Fi is the wireless network operating mode. This is perhaps the main reason for authentication errors when connecting to Wi-Fi on a phone that may not support the current mode. There can be several modes: B, G, N, etc. If you have B/G/N mixed, install it, and you can try experimenting, choosing one or the other mode. Pay attention also to the channel. It should be auto.

Security Settings

Find the security section in your router settings and try playing with the settings. It is advisable that the network authentication be set to WPA/WPA or WPA-PSK (if there is mixed, enable it), encryption is AES, the key contains only latin characters, only numbers or both.

After changing the router settings, reboot it and re-establish the connection on the phone. Unfortunately, the two methods described above can cause problems with connecting other devices, such as a laptop or TV, if they do not support the changed parameters, so everything is not so simple here. If the password has changed, in any case it will also have to be changed on other devices.

Channel width

It's highly unlikely that this will help solve the problem, but just in case you can try changing the channel width Wi-Fi networks. IN D-Link routers look for the setting in the subsection Wi-Fi Additional settings , in TP-Link – Wireless Settings – Channel Width. Available options usually several: 20MHz, 40MHz, Auto and others.

Filtering by MAC address

Each electronic device has its own unique identifier - MAC address. Find the MAC filter subsection in the router settings and make sure filtering is disabled.

If it is enabled, determine the MAC address of your smartphone, check the settings in the router and, if necessary, remove the phone from the “black” list or, conversely, add it to the “white” list.

Phone stuck on getting IP address

Another common problem is the device getting stuck at the stage of obtaining an IP address. The phone does not connect to Wi-Fi, it says “Obtaining an IP address,” and this message can appear for hours. The cause of the problem, again, may be hidden either in the settings of the mobile device or router. The latter is indicated by problems connecting to Wi-Fi and other devices. Responsible for distributing IP addresses to devices, changing the pool of addresses and the router itself in the router DHCP server. If it is disabled, your device will never receive an IP address.

Is DHCP enabled?

Let's check the operation of DHCP. The location of this setting differs in different router models. In TP-Link you need to look for it in the section The local network or LAN, in D-Link it is usually located in the subsection Network – LAN.

The mode must be selected "Allow". Instead of a drop-down menu, the “Enable” and “Disable” radio buttons can be used in the router settings. Here, we believe, everything is clear too.

Static IP

You can solve the problem of “eternally” obtaining an IP address by setting a static IP in the advanced connection settings of your device.

To do this, click on your connection in the list of networks, select Change network – Advanced settings – DHCP – Custom(in earlier Android versions you will need to check the “Static” box).

In the panel that opens, enter the IP address 192.168.X.YYY in the appropriate fields, where X is 1 or 0, this depends on the address at which you access the router settings (you can try both options), and YYY is any number from 0 up to 255.

The gateway must match the address of your router, leave the prefix length at default, do not touch DNS 1 (8.8.8.8) and DNS 2 (8.8.4.4). If you have other data instead of those indicated in brackets, do not change them either - they are given by your provider. The exception is DNS 2, which can be left blank. If something is unclear or you doubt the correctness of the data entry, it is better to contact your provider’s support service - it is their direct responsibility to connect their clients’ devices to the network.

Automatic error correction tools

If you encounter an authentication error when connecting to Wi-Fi on Android, but it works for you Mobile Internet, install from the Store Google Play application Android WiFi Fixer. This utility is an analogue of the connection troubleshooting tool in Windows and is designed to find and automatically correct Wi-Fi connection errors on mobile devices under Android control. Once launched, the application checks everything network settings and tries to connect to Wi-Fi bypassing it.

Other reasons

The above examples of problems and how to fix them are the most common. In reality there may be more reasons. Why doesn't my smartphone connect to Wi-Fi? Perhaps you installed a proxy server program that was not fully developed, caught some kind of virus, rooted the device, changed the firmware, etc. Here you need to look at the circumstances. There have been examples where wireless connection blocked antivirus programs.

In general, if the connection is lost after making some changes, most likely this is the reason. If all else fails, reset the device to factory settings, remembering to first create backups important applications and data.

Well, the most unpleasant thing that can happen is failure Wi-Fi adapter. In this case, not only yours, but also other wireless networks will not be detected. There is nothing to do here; you will have to take your gadget to the service center.

Authentication failed. How to fix authentication error when connecting to WiFi

Why does the authentication error appear?

Setting the encryption type in the router settings

Fixing WiFi authentication error:

Connect to Wi-Fi on Android:

So, wifi authentication: what is it?

Android wifi authentication error: what to do?

1. The secret code for connecting to WiFI was entered incorrectly

2. Mismatch between the connection type in the tablet settings and the Wi-Fi equipment

3. Large distance between router and tablet