USB technology is one of the most important of the many technologies that have made a huge impact in the computer world. USB (Universal Serial Bus- “universal serial bus”) - a serial data transfer interface for low- and medium-speed computer peripheral devices
This technology has made it truly easy and convenient to work with printers, scanners and external storage devices (external hard drives, USB flash drives). All actions with installing USB devices came down to a simple principle: “ 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 the maximum transfer speed to 5.0 Gbps. The USB symbol is a kind of trident, drawn both on USB devices and on computer connectors.
USB technology has already 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 damage to USB connectors, as well as devices with external damage to the case or with a clear burning smell.
If the USB ports on the motherboard are mechanically damaged, it is better to disconnect them from the motherboard (the connectors on the front of the case) or seal 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 try 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 recognized "The problem may be in the 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 a 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 easiest way to fix this sudden problem is to restart the 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 restarting the computer is not desirable at the moment (for example, because some important operation is being performed), then you can “reload” the drivers without rebooting the entire computer via device Manager. To launch it on the shortcut " My computer» right-click 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.
Updating USB controller drivers
Another reason that USB ports do not work is damage to the USB controller drivers. The only way out is to 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). Installing the 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.
This happens when USB ports on the computer stop working. In this article, we will look at common reasons that lead to this problem and solutions. The very first thing you can do is restart your computer, since frequent problems with USB ports are due to an error in the driver. If this method does not help, move on.
Perhaps the settings in the motherboard BIOS have gone wrong. If the corresponding USB controller is disabled for some reason, it must be enabled. When you start the computer, press the Del or F2 key to enter the BIOS. Next, in the Integrated Peripherals or Advanced section, we will find a similar item on the USB Controller and see what position it is in (Enabled - enabled, Disabled - disabled). So, if you have the Disabled mode set, change it to the opposite. To save the changes, press the F10 key and agree by pressing YES. After the reboot, the ports should work, if that doesn’t help, then follow the steps below.
Reasons why USB ports on a PC do not work:
- Any USB device is faulty: I recommend turning on the computer, having first disconnected everything (mouse, keyboard, printer, webcam, etc.). Leave only one working flash drive. If the flash drive starts working when you start the computer, then the peripheral devices are to blame. You can determine which one is faulty by connecting it to the computer one by one.
- ports may not work due to faulty software code. Go to the “Task Manager”.
We look carefully in the “USB Serial Bus Controllers” section; if there is a device with an exclamation mark, this indicates that it is not working properly. Double-clicking the mouse will open it, and in the window you can read information about the fault.
- Alternatively, you can remove all controllers responsible for USB, and then reboot the system. After launch, Windows will automatically install them again. After this, it is likely that the USB ports will work.
- If the problem with the ports arose due to a failure in the program code, then you can try to restore the operating system, that is, roll it back to the last checkpoint. Go to the Start menu - Control Panel. Here we find the “Recovery” section.
Next, click the “Start System Restore” button. A recovery window will open and following the prompts you can roll back the system.
- Also, a similar problem may occur due to the lack of a driver for the motherboard chipset. In this case, you need to enter this data on the manufacturer’s website. After downloading and installing the driver, you should restart your computer.
- To make sure the problem is in the system or hardware, you can boot from any Live CD. If after booting from such a disk/flash drive the ports work, then the problem is clearly in the operating system and there is only one way out - reinstall Windows. If USB does not work in the virtual system, then the problem is in the hardware. In this case, we do what is written below.
There was a case with one friend when the USB ports stopped working. Replacing the 3-volt battery on the motherboard solved this problem.
- Alternatively, you can update the BIOS. This solution helps many users. To update the BIOS, go to the official website of your motherboard manufacturer and in the “Download” section, find the latest BIOS version. There you will also find detailed instructions for updating.
- If you experience frequent problems with USB ports, I recommend installing a PCI-USB controller. A good thing that will be independent of your built-in ports.
- The last option is to have your PC repaired, where professionals will probably make an accurate diagnosis.
That's all, friends! Thank you for your attention!
Today, USB is one of the most common data transfer protocols between a computer and a connected device. Therefore, it is very unpleasant when the system does not see devices connected to the corresponding connector. Especially many problems arise if interaction with a keyboard or mouse occurs on a PC via USB. Let's figure out what factors cause this problem and determine methods to eliminate it.
In this article we will not discuss problems with the visibility of the device associated with its inoperability, because in this case this equipment should be replaced or repaired. The article will concern cases where the problem is caused by malfunctions or incorrect settings of the system or PC hardware. In fact, there can be many reasons for such a malfunction, and each of them has its own solution algorithm. We'll talk about specific ways to fix this problem below.
Method 1: Microsoft Utility
In many cases, a specially created utility from Microsoft can solve the problem with the visibility of USB devices.
Method 2: "Device Manager"
Sometimes an issue with USB hardware visibility can be resolved by simply updating the configuration in "Device Manager".
- Click "Start". Click "Control Panel".
- Come to "System and safety".
- Now open "Device Manager" by clicking on the corresponding inscription in the block "System".
- The interface will launch "Device Manager". The problematic device in the list can either be displayed in a block "Other devices", or absent altogether. In the first case, click on the block name.
- A list of devices will open. Problematic equipment may be indicated there either under its real name or listed as "USB Mass Storage Device". Click on its name with the right mouse button ( RMB) and select "Update configuration...".
- Device search will be activated.
- After it is completed and the configuration is updated, it is quite possible that the system will begin to interact normally with the problematic device.
If the required equipment is not displayed at all in "Device Manager", click on the menu item "Action" and then select "Update configuration...". After this, a procedure similar to that described just above will occur.
Method 3: Update or reinstall drivers
If the computer does not see only a certain USB device, then there is a possibility that the problem is due to incorrect installation of drivers. In this case, they need to be reinstalled or updated.
If this option does not help, then there is another method.
- Click in "Device Manager" by device name RMB. Select "Properties".
- Go to the tab "Driver".
- Click on the button "Roll back". If it is not active, click "Delete".
- Next, you should indicate your intentions by pressing the button "OK" in the dialog box that appears.
- The procedure for removing the selected driver will be performed. Next, click on the position in the horizontal menu of the window "Action". Select from the list "Update configuration...".
- Now the device name should appear in the window again "Device Manager". You can check its functionality.
If the system was unable to find the appropriate drivers or the problem was not solved after installing them, then you can use the services of specialized ones. They are good because they will find matches on the Internet for all devices connected to the PC and perform automatic installation.
Method 4: Setting up USB controllers
Another option that can help solve the problem under study is setting up USB controllers. It is still performed in the same place, that is, in "Device Manager".
If this does not help, then you can reinstall the drivers for the group elements listed above "USB Controllers", using the same methods that were described in the presentation Method 3.
Method 5: Troubleshooting the port
It is possible that your computer does not see USB devices simply because its corresponding port is faulty. In order to find out if this is so, if your desktop PC or laptop has several USB ports, try connecting the equipment through a different connector. If this time the connection is successful, it means that the problem is in the port.
To resolve this problem, you need to open the system unit and see if this port is connected to the motherboard. If it is not connected, then connect. If there is mechanical damage or other damage to the connector, then in this case it is necessary to replace it with a working version.
Method 6: Relieving Static Stress
In addition, you can try to remove static voltage from the motherboard and other PC components, which can also cause the problem we are describing.
There is also a possibility that the computer does not see the equipment due to the fact that many USB devices are already connected to it. The system simply cannot cope with such a load. In this case, we recommend that you disconnect all other devices and connect the problematic equipment to the back of the system unit if there is an appropriate connector there. Perhaps this recommendation will help solve the problem.
Method 7: Disk Management
The problem with the visibility of a connected USB device, in this case exclusively a flash drive or external hard drive, can be solved using the system’s built-in tool "Disk Management".
- Click Win+R. Enter in the field of the shell that appears:
Apply by pressing "OK".
- The tool interface starts "Disk Management". You need to monitor whether the name of the flash drive appears and disappears in the window when it is connected to the computer and disconnected. If nothing new happens visually at all, then this method will not suit you and you need to solve the problem using other methods. If changes occur in the list of connected drives when attaching new media, then you can try to solve the problem with visibility using this tool. If next to the name of the disk device there is an inscription "Not distributed", then click on it RMB. Next, select "Create a simple volume...".
- Will start "Simple Volume Creation Wizard...". Click "Further".
- Then a window will open where you need to specify the volume size. Since in our case we need the volume size to be equal to the size of the entire disk, then click here too "Further" without making changes.
- The next window requires you to assign a drive letter. In the corresponding field, select a character that differs from those letters that are already assigned to other drives in the system. Click "Further".
- The following settings window opens. Here in the field "Volume Label" You can enter a name that will be assigned to the current volume. Although, this is not necessary, since you can leave the default name. Click "Further".
- The next window will provide a summary of all the data entered in the previous steps. To complete the procedure, just click on the button "Ready".
- After this, the volume name and status will appear opposite the media name "Fixed". Next click on it RMB and select “Make partition active”.
- The computer should now see the flash drive or external hard drive. If this does not happen, then restart your PC.
There are situations when when opening a tool "Disk Management", the volume that belongs to the flash drive already has the status "Good". In this case, there is no need to create a new volume, but only those manipulations that are described starting from point 8 need to be performed.
If, when opening the tool "Disk Management" you see that the disk is not initialized and has a single volume that is not allocated, this means that, most likely, this drive is physically damaged.
Method 8: Setting up the power supply
You can solve the problem with the visibility of USB devices by making some manipulations in the power settings. This method especially often helps when using laptops that interact with connected equipment via the USB 3.0 protocol.
- Go to "Control Panel" and then to the section "System and safety". We discussed how to do this during analysis. Method 2. Go here by position "Power supply".
- In the window that opens, find the current power plan. There should be an active radio button next to its name. Click on the position "Setting up a power plan" near the named position.
- In the shell that appears, click “Change advanced settings...”.
- In the window that appears, click "USB Settings".
- Click on the inscription "Temporary shutdown option...".
- The specified option will open. If the value is specified there "Allowed", then you should change it. To do this, click on the indicated inscription.
- From the drop-down list, select "Forbidden" and then click "Apply" And "OK".
Now you can check whether USB devices will work on this PC or whether you need to move on to other ways to solve the problem.
Method 9: Eliminating the virus
We should not exclude the possibility that the problem with the visibility of USB devices arose as a result of a virus infection of the computer. The fact is that some viruses specifically block USB ports so that they cannot be detected using an anti-virus utility connected from a flash drive. But what to do in this situation, because if the standard antivirus missed the malicious code, then it is now of little use, and you cannot connect an external scanner for the above reason?
In this case, you can scan the hard drive with an anti-virus utility from another computer or use a LiveCD. There are quite a few programs designed for these purposes, and each of them has its own nuances of operation and management. But there is no point in going into detail about each of them, since most of them have an intuitive interface. The main thing when detecting a virus is to follow the prompts that the utility displays. In addition, our website has a separate article dedicated to such programs.
There are quite a few ways to restore the visibility of USB devices in Windows 7, but this does not mean that all of them will be effective in your particular case. Often you have to try many options before finding the right way to solve the problem.
Various failures and malfunctions may occur in the operation of computer equipment from time to time. Many users often look for an answer to the question: why doesn’t the USB port see the device? In fact, connecting USB devices to your computer may not be detected by the Windows operating system due to an error occurring.
Who is to blame and what to do?
The first place to start to find out the reasons for this “behavior” of the system is to check the serviceability of the device connected to the computer. You can use another device for this.
If the error repeats on another computer, we can conclude that the cause is the connected USB device. Whether to send it in for repairs or buy a new one is a decision at your discretion.
One of the reasons for the error may be the presence of bad contacts. Long-term use of wired mice and keyboards is usually to blame for this. Repeated kinking of the cable can damage the inner wire and lead to this problem.
Very often the error occurs due to static electricity. USB devices are a kind of storage of electrical charge, so when they are connected to computers, an electrostatic field often arises and the voltage increases. In this case, the protection system is activated, and all ports for connecting USB devices are automatically disabled.
How to fix the problem?
There are several ways:
- First of all, you need to disconnect the computer device from the power supply. If such a problem occurs with your laptop, you must remove it from the battery. When the above steps are completed, wait 5-10 minutes, return the battery to the laptop, and connect the computer to the network. To your surprise, the ports will work!
- You can use another method to solve the problem. If the error occurs due to several simultaneously connected USB devices, you need to disconnect them. Then the device that was not recognized must be connected to the computer again. As practice shows, this method is effective.
- If the above methods do not provide the desired result, you can use another one. One of the reasons for the error may be incorrect driver installation. The problem can be resolved by disconnecting all USB devices from the computer ports. After this, you need to find Windows 7 C:\Windows\System32\DriverStore\. and delete the INFCACHE.1 file on your computer.
The next time you connect the flash drive, a new correct file with exactly the same name is created.
We hope that the above information will be useful to you and help in solving the problem.
Quite often people come to us asking why the USB ports on their laptop or computer do not work. USB ports may stop working after reinstalling Windows, after updating drivers, or at any inopportune moment. Of course, the problem may be faulty USB ports, but before taking your laptop/computer to a service center, you should check the settings to make sure that the problem is not in the software.
So, let's see what you can do in a situation where the USB ports on your computer or laptop are not working.
Check USB ports
The first thing you need to do is check the USB ports for physical damage.
A simple test is this: insert a USB device into a port on your laptop and see if the connected device moves up and down easily. Be careful! You should not yank the USB port too hard to avoid breaking it.
If the USB port moves too freely, the problem is likely due to physical damage. You should contact a service center to replace the USB port.
To restart a computer
You can also try the good old method of any technical support department: turn it off and on. Sometimes this actually works because the operating system rescans the hardware, including USB ports, making them work.
If this doesn't help and the USB ports are still not working on your computer, then it's time to check the Device Manager.
Check Device Manager
You can run device Manager several ways, but we'll tell you about the fastest one: press the Win + R keys and enter devmgmt.msc. Click "OK" or key « Enter». Device Manager should immediately appear on your computer screen.
In this window we are interested in the section “ USB controllers" Click the arrow next to this label to expand the section. You will see something like the window below:
Here you should find a device that has words USB Host Controller in its title. For example in my case it is Intel(R) 5-Series/3400 Series Chipset Family USB Enhanced Host Controller. Some letters may be different for you, but in general you should have a similar device. If it simply isn't there, that's probably the problem why the USB ports on the laptop aren't working.
In this case, you should right-click on “ USB controllers» and select "Update configuration" The computer will recheck the hardware and you will see USB Host Controller in the list.
Remove USB Host Controller
Next, you need to act carefully. If you are working on a computer, then most likely you have a USB mouse and keyboard connected. After you remove USB Host Controller, your mouse and keyboard will not work. This is not a problem as they will work again after rebooting your computer.
So, as you understand, you should right-click on the USB Host Controller device, and select “ Delete" Perform this step for all devices named USB Host Controller.
After removing USB Host Controller, restart your computer or laptop. After restarting, the computer will automatically install the necessary drivers for the USB ports to work.
Find the DisableSelectiveSuspend registry key
If the USB ports are still not working, then we will go one step further and make some changes in the Registry Editor.
To go to the Registry Editor, press the keys Win+R, enter regedit, and press the " Enter" The Registry Editor window will open.
Next you need to find the registry key DisableSelectiveSuspend. It is located in the following folder: HKEY_LOCAL_MACHINE -> SYSTEM -> CurrentControlSet -> Services -> USB. Next, in the right window, right-click on the file “ DisableSelectiveSuspend", and select " Change».
In field " Meaning» enter number 1 . This way you will disable the Selective Suspend feature and power will always be supplied to your USB ports.
If there is no USB folder
If the USB folder doesn't exist in your registry, it's easy to create one. Just go to the Services folder, then on the toolbar click " Edit»> « Create»> « Chapter" Name it USB.
Next, select the new USB partition, right-click in the empty window on the right. You will only have the option " Create" Click on it and select the value " DWORD value (32-bit)" Enter the title DisableSelectiveSuspend.
As we wrote above, right-click and select "Edit". In the Value field, enter the number 1. For the changes to take effect, you need to restart your computer.
Ready! Our tips should help in a situation where the USB ports on your computer have stopped working. If you know other reasons why USB ports on a laptop do not work and how to fix it, write in the comments below.