If USB doesn't work. Disabling other connected USB devices

So, first you need to clarify - USB stopped working on computer or USB stopped working on laptop. The strategy in each case will be slightly different, and the sequence of actions will also be slightly different. self-diagnosis and restoring the correct operation of the universal serial bus controller (USB, Universal Serial Bus).

Diagnostics of USB in a computer and methods for repairing it

If they stopped working Computer USB, it is necessary to carry out a number of activities:

• If USB on the front panel of the case does not work desktop computer , then a mechanical failure is more likely to occur;
• or at USB connection housing system unit(4 wires; 2 of which are signal, and 2 provide power) an error occurred to the connectors on the motherboard (the so-called front panel) - the USB is not connected correctly (the polarity or the sequence of the data transfer wires is incorrect);
• to check the correct connection and avoid more serious damage motherboard computer must be connected working device, for example a flash drive, to the connectors located on the back of the system unit - USB motherboard. At the same time, never rush to connect devices to the front panel - there is a risk of burning the flash drive if the polarity is not observed.
• Thus, if the flash drive is detected at the back of the system unit, but does not want to work at the front, we conclude that the contact in the USB panel is broken (the soldering at the junctions with the wire and the connector itself often breaks off), it is damaged USB connector (this fact easily detected by visual inspection), the USB hub connector on the motherboard is not connected correctly or is not connected at all; to do this, you will have to remove the protective casing of the system unit and assess the condition, armed with a manual with the correct indication of the connection sequence.

For each motherboard, it is better to look at the sequence separately, since there is a direct sequence (reverse), a horizontal position of the block and a vertical one. It is worth paying attention to the colors of the contacts and the block (if it is painted in some way), or the colors of the contacts and their location relative to the metal contact pins of the block (especially the missing pin).

If connecting to the USB connectors on the motherboard did not give anything, you should pay attention to the color of the USBs themselves - black or blue. If the USB to which the flash drive is connected is blue (the plastic inside the connector itself is painted blue as in the picture), then this indicates that we are trying to work with a USB 3.0 port. This is a more powerful connector in all respects, but also more problematic. The point is that such USB connectors may not work after Windows reinstallation without separate drivers, or does not work correctly with some devices even if they are available. This situation can lead to both the inability to work and various types of failures - blue screens and computer freezes.
Therefore for full diagnostics We look for the black USB connector and connect to it. If the device is detected, we conclude that the problem is with the drivers for USB 3.0. To fix this problem, install the drivers from the motherboard kit or, best of all, download them from the manufacturer’s website.

If devices are not detected in any of the USB ports, then perhaps the reason is in the controller, then purchasing separate device called expansion card USB2.0-PCI or USB3.0-Mini PCIe, since repairing a USB controller for a computer motherboard is not cost-effective. The boards cost differently and differ in speed characteristics and power supply.

USB2.0 board is traditionally cheaper, less speed, suitable for old computer; but may not fit into the new one, with motherboard MicroATX format (small board with one PCI connector).

USB3.0 boards are usually more expensive, more powerful and faster, but are not suitable for an old computer; can be used if PCI slots are occupied or obscured by a video card.

Here is a set of work to diagnose and restore functionality for a USB computer - for a laptop it may be somewhat more complicated (or easier).

Self-diagnosis and repair of a USB laptop

Diagnostic and repair algorithm laptop usb similar to the same one on a computer, but there are some features. Firstly, the diagnosis is very simple, and secondly, the repair is quite complicated. I would like to immediately warn you that accurate diagnosis is best carried out after complete reinstallation Windows, since there is a possibility of a previous installation of drivers and recording of erroneous parameters, which will lead to the impossibility of restoring correct operation laptop.
Diagnostics consists of testing the operation of the black and blue connectors on the laptop (USB2.0 and USB3.0). If USB3.0 does not work— we try to connect the USB flash drive to connector 2.0 (black), if USB2.0 works, we conclude that we need drivers for USB3.0. It is best to use official sources with drivers for these purposes, i.e. laptop manufacturers' websites. Various drives Auto-installation of drivers may or may not help. Therefore we need high-quality repairs laptop - be prepared to push yourself (this applies to everyone).
If you find that even after reinstalling Windows, none of the existing USB ports work, that’s bad. One hope is that someone simply turned them off through bios - go into bios and turn them on. Otherwise, most likely the controller has failed or there are problems with the south bridge of the laptop motherboard. In any case, a complex laptop repair will be required - which can only be carried out in service center.

Naturally, before this it is necessary to exclude mechanical damage to the laptop’s USB ports, which can also lead to short circuits. This situation will be characterized by the following phenomena: the laptop turns off when USB is connected, or the laptop turns on and immediately turns off. Mechanical damage can be assessed visually by looking into the slot of the connector: if all the hardware is in place, everything is in order. Moreover, you will have to inspect all the connectors, and not just where you want to attach the flash drive. If a problematic connector is detected, the laptop will need to be repaired -.

A number of laptop users may encounter a situation where the USB ports on the laptop do not work, and devices connected through them are not recognized Windows system. This problem occurs quite often, and can have many reasons, making it difficult for the user to work with the USB devices he needs on his computer. In this article I will tell you why they don't work USB ports on a laptop, what are the reasons for this phenomenon and how to fix it.

So, why did the USB ports on the laptop stop working? The reasons for this dysfunction may be the following:

How to fix non-working USB ports

In order to fix non-working USB ports on a laptop, you need to do the following:

• Restart your laptop. It is recommended to turn it off completely, remove battery for a few minutes, then return it back and boot the operating system again;
• Inspect the USB connectors of your laptop, if necessary, clean them from dust using a regular wooden toothpick;
• Try connecting your device to another USB connector; perhaps the first connector is no longer functioning;
• If you are connecting your USB device via a cable, try changing the latter, this may help the problem when the USB ports on the laptop do not work;
• Make sure that the connected USB device works; to do this, connect it to another computer;
• Go to BIOS and make sure that the USB functions are enabled;

  

• Manually recognize USB devices using the system. Click on the Start button, type devmgmt.msc in the search bar and press enter. Device Manager will appear in front of you, click on the name of the list of devices at the top (usually the name of your computer), click on the “Action” tab, and select “Update hardware configuration” there. If the system finds USB controllers during this procedure, then your problem can be solved;

  

• Remove and then reinstall the USB controllers. Go back to Device Manager as described above, find “USB Controllers” there, and double-click on this entry. A list of USB controllers will open in front of you, right-click on the first one and select “Delete”.

  

• Similarly, delete all controllers in the list. Then restart your PC, these controllers will be automatically installed by the system again, this can help fix the problem when the USB ports on the PC do not work;
• Reinstall the drivers for the USB. Usually, the laptop comes with a disk with drivers, including a USB driver; you just need to install it on the computer and the problem will be solved. If your USB connection is highlighted question mark or has the status “unidentified device”, then you need to find out the ID of your device, and use this ID to search for drivers on the network;
• If you have several connected USB devices, then try turning them off and leaving only what is needed at this moment;
• Download and run a special utility from Microsoft, it can help fix problems with USB if the USB ports on the laptop are not functioning;
• Perform a system rollback to a previous working restore point (). Click Start, type rstrui in the search bar and press enter. Find a restore point at which the system worked correctly and perform a rollback;

  

• If everything doesn't work for you USB ports and the above methods didn't help, then maybe you're burned out south bridge. Its replacement (or warming up) is carried out at a service center using special equipment; contact them for advice and assistance.

Video solution to a situation where the USB port does not see the device

In this material, I examined a situation in which the USB ports on a laptop do not work, listed a list of reasons for this dysfunction and provided a number of tips for solving it. If you don't know what exactly caused it mentioned problems with USB ports, then consistently follow the entire set of tips I have listed, this will help to effectively solve the problem with malfunctioning USB ports on your PC.

In contact with

USB technology is one of the most important of the many technologies that have had a huge impact in computer world. USB (Universal Serial Bus- “universal serial bus”) - serial interface data transfer for low- and medium-speed computer peripherals

This technology has made it truly easy and convenient work with printers, scanners and external devices data storage ( external hard disks, USB flash drives). All actions with USB installation devices have been reduced to the simple principle of “ Plug and play" Devices have become truly mobile precisely because of USB technology. Today, not only desktop PCs and laptops are equipped with USB ports, but also gaming devices, smartphones, cameras, navigators and many other devices.

Ports USB version 2.0 provide data transfer at speeds up to 480 Mbit/s, and the version USB 3.0 raises maximum speed transfers up to 5.0 Gbit/s. The USB symbol is a kind of trident, drawn both on USB devices and on computer connectors.

Technology USB already has been studied quite seriously and has undergone many improvements, so USB ports, when used correctly, rarely cause any problems, and troubleshooting problems associated with them does not cause much trouble. This article will outline the basic principles of troubleshooting USB ports.

But before we begin, it’s worth describing basic recommendations when working with USB ports and devices, connected to them:

- never connect devices with visible mechanical USB damage connectors, as well as devices with external damage to the housing or with a clear burning smell.

If the USB ports on the motherboard have mechanical damage, then it is better to disconnect them from the motherboard (the connectors on the front of the case) or cover them with colored tape to prevent their use. If necessary, it is better to replace such ports in a workshop with new ones.

Try not to overload USB ports. Their current strength is strictly limited: 500 mA for USB 2.0 and 900 mA for version 3.0. Do not strive to increase the number of USB ports using various USB multipliers. Modern motherboards already have up to 10 ports, which is quite enough for home use. It is always safer to buy an additional PCI or PCIe USB controller than to work through a USB “tee”.

If the USB ports on a laptop stop working, then working on it becomes very difficult - you cannot connect a printer, a scanner, or a flash drive. And unlike a desktop computer, installing an additional USB controller is very expensive.

In many cases, when the error message " USB device not identified "The problem may be precisely USB port. This problem is usually solved quite easily, since it occurs mainly at the software level.

What to do if the USB ports do not work?

Any hardware device interacts with the installed operating system through special program - driver. Many problems with devices are solved with the help of drivers. The same is the case with non-functional USB ports. Below are several methods that will help you troubleshoot USB ports at the software level.

If the USB ports suddenly stop working, and USB devices are not detected, then the most in a simple way The solution to this sudden problem will be to restart your computer. Just restart your computer. If there were no problems loading the drivers, this problem will be resolved after a reboot.

Update hardware configuration in Device Manager

If you restart your computer in this moment is not desirable (for example, due to performing some important operation), then you can “reload” the drivers without rebooting the entire computer via device Manager. To launch it on the shortcut " My computer» click right click mouse and select the menu item " Management e". Or in the menu " Start» find the program « Execute"and after launching it, enter the command devmgmt.msc.

In the window that opens, left-click once on the list of devices and then click the tab " in the main menu Action", then point to " Update hardware configuration" See if the section " USB controllers" If yes, then your problem is solved, the USB ports should work.

Another way to get USB ports to work is to unplug and then reinstall the USB controller. To do this you need to run again device Manager. In the list of equipment that you will see in the window that opens, find the USB controllers section. On each of the devices in this section, right-click and delete them all. Once you remove all controllers, simply restart your computer. The controllers will be reinstalled and the USB ports will become available again. This may solve your problem.

Update USB drivers-controllers

Another reason that USB ports do not work is damage to the USB controller drivers. The only way out- find the correct drivers and reinstall them. To download the appropriate driver, you need to find out the manufacturer of the USB device port (via it). Installation correct driver should solve this problem in an instant.

Disabling other USB devices

Sometimes USB ports do not work due to overload when too many USB devices are connected. USB hubs sometimes do not provide enough power to the devices connected to it. The connected device can consume all the permitted power of the computer's USB controllers. If the equipment is connected to a USB hub, then simply connect the device directly to a USB port on your computer.

You can also leave the device connected to the USB hub, but first disconnect other devices in the hub. For the future, purchase a USB hub with its own power supply that will provide sufficient power to all devices connected to it.

If none of the above methods worked, then it is likely that the USB ports were physically damaged. Or the USB controller, in particular the south bridge of the motherboard, is damaged. In this case, the best thing you can do is replace or repair the USB port controller at a service center.

Hello, dear readers! Every time you start the computer, all devices installed in the computer are initialized, data about drivers and various utilities is read. But, sometimes there comes a time when the device connected to personal computer, is not detected by the operating system.

It is at this point that we have an anxious moment and wonder why does not workUSBport? What exactly is the matter and what needs to be done to make the port work? In the end, as they say, there is a way out. But first, let's figure out how everything works and what the essence of this material is.

So, many of us use the USB port constantly when working on a computer, as if it is impossible to do without it, although in fact it is so. In computers, as you know, USB ports are present not only on the front panel, but they can also be seen on the front panel of the system unit case, for example in the card reader.

So, at present, the USB port is the heart of the system, so to speak, the exchange of information that can be transferred at any time to the PC system available at that time. I am already silent about the fact that using ports it is possible to enter data into a computer (mouse, keyboard). The location of ports on a personal PC is always different, it is worth adding that in advanced systems, gaming platforms, additional USB ports are installed.

As always, as it usually happens, one fine day a moment comes when the USB port does not work, that is, the USB port simply hangs, glitches, is not detected by the system, or rather, it does not work correctly. In today’s article, I suggest you consider the reasons, as well as solutions, for a non-working USB port.

We wonder why the USB port does not work?

Firstly, if when you connect a flash drive to a computer or some other equipment, the port does not work quite correctly or the device connected to the computer is not detected by the system at all, then in this case you should make sure that the controller on the PC motherboard is turned on .

Quite often, users forget to turn on the USB controller. It seems like a simple, but still common problem when the user starts the PC, but the device is not detected. It is possible to fix everything here; to do this, you need to go into the BIOS and enable the appropriate parameter. By the way, if you don’t know what a BIOS is, then I recommend that you definitely read the article

So, go to the BIOS and find the item “Integrated Peripherals - this applies to Award BIOS", or in Ami BIOS- Advanced.

Next, press “Enter” and go to “Onboard Devices Configuration” and make sure that the “USB Function” and “USB 2.0 Controller” items are in the “Enabled” position. If everything is so, then everything is included. Otherwise, the parameter can be turned OFF, position “Disabled”. If the option is disabled, you should enable it. Next, save the changes, then reboot the PC system and check the functionality of the USB port. Be sure to check whether the USB ports on the front panel of the system unit are connected to the motherboard itself using the so-called connector.

If the port still doesn’t work, then we move on.

Secondly, or maybe the problem is that the port is not working and is completely hidden in the USB extension cable? For example, there are situations when the computer does not recognize a peripheral device (printer), for the simple reason that it USB cable just damaged. The reason for cable damage can be very varied, for example, you accidentally placed a chair on the cable or some heavy object and simply pinched it. Therefore, do not be lazy to check the cable itself.

Third, it is quite rare to encounter such a problem when the USB port does not have enough power. I'll give you specific example. Imagine that you have connected a flash drive and a printer to the front of the system unit case in the USB connector. As a result, the operating system, when sending data for printing, informs us that the document could not be printed. In general, your computer simply does not see the printer. And if you restart the computer, the printer is detected by the system, and you can easily print a document. However, after a while, the computer again loses connection to the printer and the printer does not print. Do you know why?

This seemingly trivial problem at first glance is due to the fact that there is a lack of power for the USB port. As a result, the USB port refuses to function properly. Basically, such an incident associated with a lack of power occurs when connecting several devices to the front panel of USB ports.

Of course, not always, but such situations still occur. These USB ports are connected to the motherboard using a cable. In addition to transmitting data, this cable also powers the USB hubs themselves. It is possible that the power supplied simultaneously to two devices connected to the USB hub may not be sufficient. In this case, I can recommend that you connect the printer to the built-in USB port, which is located on the PC motherboard.

You can also change the CMOS battery on the board. It happens that the problem completely disappears after replacing the battery on the motherboard. What kind of battery is this and where it is located, you can find out in this article:

In general, if you have does not workUSB port, which is located on the front panel of the system unit case, then try replacing the USB hub itself. Who knows, maybe it is the one that is faulty.

You can also try plugging the cable into another USB connector on the motherboard.

Fourth, if the USB port controller, which is responsible for identifying and starting the device itself, has failed, then things are, of course, bad. There is, of course, the opportunity to take and resolder the controller itself on the motherboard, but this takes time, you need to have the controller itself, and, of course, the soldering station itself. From a time-cost point of view, it is not entirely advisable. Another option is to entrust it to specialists, although this also has its pitfalls, price, quality of work, as well as the competence of the specialist who specifically works on this problem.

Fifthly, peripheral and mobile devices may not be recognized on your computer due to the lack of drivers and special software. We cannot exclude the fact that if you have been using your operating system for quite a long time and the system has not been updated at all, and indeed Windows assembly is not the original version, then in this case it happens that the drivers are considered outdated and therefore the system constantly freezes.

Sometimes Windows disables the USB hub altogether to save power. To prevent the USB device from being disconnected, you will need to do the following.

Open “Device Manager” by right-clicking on the “Computer” shortcut and selecting “Properties”.

After the Device Manager window has opened, double-click with the left mouse button on “USB Controllers” and expand the branch.

Now all you have to do is go to the root USB hub and in the “Power Management” section uncheck the box, as shown in the figure below.

At sixth, sometimes reinstalling the operating system helps fix the problem when does not workUSBport. Although, of course, first try to perform a system rollback to previous state. Here is an article that will tell you how to do this:

Seventh, perhaps there is some kind of faulty equipment, which precisely serves as an obstacle to normal operation USB port.

This problem is very relevant in our time. After all, quite often users directly encounter this. So, there is a solution. USB ports on your computer may freeze, contacts may short out, and many more. additional problems may occur when working at a computer.

We find a way out of our situation, check all devices for connection and disconnection. You will need to disconnect all devices and connect one at a time, for example, connect the keyboard first and see if it works, then connect next device, let it be a mouse and so on. Connect additional USB devices, if they don’t work, then the problem is solved or you need to look in peripheral devices, maybe there’s something shorting there, but who knows.

Eighth, they completely forgot to enable the serial bus controller in the device manager. There are times when you don't pay attention to USB operation devices, turned on the computer, downloaded music, listen and enjoy new works of art. True, everything comes unexpectedly, suddenly you need a USB device, and then there is silence, it doesn’t work. The thought immediately comes to mind, maybe the controller is not turned on, let me take it and check, it is so.

Each PC has a device manager that shows which devices are connected, whether all drivers are installed and updates made.

In general, I think that you probably already know that if any driver is missing, the system automatically marks it in yellow exclamation mark, this means a malfunction, as a result, with two clicks of the mouse you open additional window, information about the fault code and the possibility of restoring it is displayed here.

Ninth, if all the above methods did not give positive result, then I recommend that you install a USB PC controller on the motherboard.

If your computer has a low-power power supply, for example 300 W, then it is likely that the cause of all the troubles is hidden in it, install a more powerful power supply, say 500 W, and check if the USB ports are working.

Concluding today's article, I would like to say that it is not always possible to easily find the culprit of all problems, sometimes it is not enough to simply reinstall Windows to find out what really happened.

If there are no drivers for serial bus controllers and the controllers themselves are marked with an exclamation mark, in this case you should either install drivers for the controller, or you can remove all controllers and restart the computer. After the computer boots, the system will try to install them again, and perhaps all USB ports will work properly again.

So, to summarize today’s article, we can only note that if the USB port on the computer does not work, then the cause of all the troubles may lie in both hardware and software. In general, I have said everything I wanted to tell you about today.

How do you like today’s article and what can you add to everything said above? In the next issue you will find out =>

Probably, many users, when connecting a flash drive or other peripheral device, have encountered a problem when the computer does not see them. Opinions on this matter may vary, but provided that the devices are in working order, most likely the problem is the USB port. Of course, additional sockets are provided for such cases, but this does not mean that the problem does not need to be solved.

To perform the actions described in the article, you do not have to be computer genius. Some of them will turn out to be completely banal, others will require some effort. But, in general, everything will be simple and clear.

Method 1: Checking port status

The first cause of malfunctioning ports on a computer may be that they are clogged. This happens quite often because there are usually no plugs for them. You can clean them with a thin, long object, such as a wooden toothpick.

Most peripheral devices are not connected directly, but via a cable. It is this that can interfere with data transmission and power supply. To check this you will have to use another cord that is known to work.

Another option is a breakdown of the port itself. It should be excluded before performing the actions described below. To do this, you need to insert the device into the USB socket and shake it slightly different sides. If it sits loosely and moves too easily, then most likely the reason the port is not working is physical damage. And only replacing it will help here.

The simplest, most popular and one of the most effective methods To resolve all sorts of problems with your computer, you can reboot the system. During this process, the memory, processor, controllers, and peripherals are given a reset command and, when executed, are returned to their original states. Hardware, including USB ports, are rescanned by the operating system, which can make them work again.

Method 3: BIOS Setup

Sometimes the reason lies in the motherboard settings. Its input and output system (BIOS) is also capable of enabling and disabling ports. In this case, you need to go into the BIOS ( Delete, F2, Esc and other keys), select a tab "Advanced" and go to point "USB Configuration". Inscription "Enabled" means the ports are enabled.

Method 4: Updating the Controller

If the previous methods did not bring a positive result, updating the port configuration may be a solution to the problem. To do this you need:

The absence of such a device in the list may cause a malfunction. In this case, it is worth updating the configuration of all "USB controllers".

Method 5: Removing the controller

Another option involves deleting "host controllers". You just need to take into account that in this case the devices (mouse, keyboard, etc.) connected to the corresponding ports will stop working. This is done as follows:

In principle, everything will be restored after updating the equipment configuration, which can be done through the tab "Action" V "Device Manager". But it will be more effective to restart the computer and, perhaps, after automatically reinstalling the drivers, the problem will be solved.

Method 6: Windows Registry

The last option involves making certain changes to the system registry. You can perform this task as follows:

File "Start" may be missing according to specified address, which means it will have to be created. To do this you need:

All the methods described above really work. They were tested by users whose USB ports once stopped functioning.