Peripheral devices such as a mouse, keyboard, webcam, printer are usually connected to the computer via USB ports. In this case, it often happens that one or more ports stop working. That is, when connected to a computer, for example, a flash drive, it is not recognized, the keyboard or mouse may freeze, and the printer may not respond and print pages.
There are several likely reasons why some or all of the USB ports on your computer are not working. Let's try to understand this issue and find out what should be done to restore the normal functioning of the computer.
Checking the BIOS settings
The first thing to pay attention to is BIOS settings computer. You will need a working keyboard to enter the BIOS. If the keyboard is connected to the computer via USB and it does not work, then you need to connect a keyboard with a PS / 2 connector. Otherwise, you simply cannot do anything.
So, we go into the BIOS, for which, when starting the computer, you must press the enter key, usually it is DEL. There may be another key that is displayed on the screen and is indicated in the manual for motherboard. After entering the BIOS, find the section responsible for the integrated devices (Integrated Peripherals) or the "Advanced" section. Here you should find the subsection “Onboard Devices Configuration”. It is in it that the parameters are responsible for USB operation controllers: USB Function or USB 2.0 Controller. These parameters must be enabled (Enabled). And if one of them is disabled (Disabled), then hover over it and press Enter, thereby enabling it. To prevent your changes from being reset, you must save them by pressing F10 and confirm the save by pressing the Y or Enter key.
After rebooting the computer, check if the USB ports are working. And if not, then you should look for the cause elsewhere.
USB ports on the front of the computer do not work
As a special case, USB only on the front panel may not work for you. In such a situation, it is necessary to check whether the necessary connectors on the motherboard are connected and whether the wires are damaged. To do this, open the side cover of the system unit and pay attention to the connector at the bottom of the motherboard. The board itself has the inscription USB1 or USB2, as well as on the block itself. The wires from the block go to the front panel, and if they are disconnected or broken in one place, then you have found the cause of the malfunction. Damaged wires should be connected or replaced. It will not be superfluous to check the contact in the connector on the motherboard. It is also worth paying attention to the board located on the front panel. Possibly takes place short circuit By the way, such a short circuit can be provoked by accumulated dust. So be sure to clean system unit from dust.
Problems with the device itself or the cable
The next source of USB problems can be the cable connected to, for example, a printer. This error is easy to identify and fix. We connect a USB flash drive to the checked connector. If it works, then we try to connect other known good equipment using a suspicious cable, for example, a USB hub. If it also refuses to work, then the reason is definitely in the cable and it should be replaced.
Power outages
There are situations when there is simply not enough power for all devices. For example, when connecting external hard A drive that uses two USB connectors at once may disable the printer or keyboard. In this case, the power of the power supply is not enough to provide energy to all consumers. In this case, the problem may not appear immediately, but after some time after turning on the computer. There are several ways out of the situation. If you have a low-power power supply installed, for example, 300 W, then it would be logical to change it to a more powerful one, 450-600 W. You can also use an active USB hub (with external power). It will allow not only to increase the number of connected USB devices, but also to power them from a separate power supply.
Another reason affecting USB performance is a dead CMOS battery. But at the same time, every time you turn on the computer, you will observe the system time and date that have gone astray. After replacing the battery, the problem goes away. But this is not common, so you should check other possible sources of malfunction.
Missing or incorrect installation of USB drivers
Causes related to software malfunctions in Windows 7/10 can be identified using the Device Manager. If you notice that one or more devices specifically do not work, regardless of the port used, then this may indicate that the problem is in the device itself. Open the Control Panel and go to the Device Manager section. All connected devices will be displayed there. If there are items in the list that have yellow next to them Exclamation point or instead of the name is unknown device, then the problem is in this device itself. There may be several possible problems here.
Often USB inputs stop working after reinstalling Windows 7/10. The reason is incorrect installation of drivers or required drivers may not be found at all. You will have to select and install manually.
Often, to fix a problem, you just need to update the drivers. Yes, if disabled automatic update Windows, and the system itself was installed a long time ago, then the relevance of the software is lost, may appear system errors. At the same time, the device starts to work incorrectly, or even stops functioning altogether. To update (reinstall) the USB controller drivers, you can use the motherboard driver CD/DVD or download the necessary drivers from the motherboard manufacturer's website.
You can also turn off the power saving feature for all ports using the Device Manager. Expand the list of used USB devices hidden in the USB controllers, Mouse and other pointing devices, Keyboards sections. Double-click on the desired device to open the properties window. Now switch to the "Power Management" tab and uncheck "Allow the computer to turn off this device to save power." Thus, the device will be activated always and under any circumstances.
If some equipment is not recognized, then there may be a problem with the drivers already known to us, as well as a hardware problem, consisting in a lack of contact, cable damage, or a controller malfunction. Moreover, it often happens that when a faulty device is connected, the rest stop working normally. The keyboard starts to freeze, as does the mouse, and the printer stops printing. The problem is similar to a lack of power, that is, the consumption of all power goes to a faulty device, which may have an ordinary short circuit or other malfunction.
USB ports not working due to damaged controller
If none of the above actions helped restore the USB ports, then you should check the motherboard USB controller, which could have failed. High-quality repairs and diagnostics in this case should be entrusted to specialists. service center. As a way out of the problem, try installing an expansion board, the so-called USB PC controller, which is installed in the PCI slot on the motherboard. This solution is much cheaper than repairing the USB controller of the motherboard, and when using an additional USB hub, the problem with the lack of ports will not be relevant at all.
As you can see, finding and fixing problems with USB ports is a rather troublesome business, and all because there can be a lot of reasons. Consistently finding and eliminating obviously wrong paths will allow you to identify and fix the problem.
In fact, there are quite a few ways. Each of them has its own advantages, and some are completely irreplaceable.
Who needs it?
First of all, administrators. And also if the computer is used by several users.
Why is this needed?
For security, for privacy, to restrict other users.
My material, as usual, is divided into two parts: system tools and third party programs(plus a little bit of my personal opinion).
How to disable the use of flash drives?
Directly in Windows, this task can be performed using the Group Policy Editor (GPO) and the registry. In addition, you can turn off the ports themselves in the BIOS. To all this, plus the external software which I will talk about at the end.
Inefficient ways to ban flash drives
In order not to dwell on this later, I will immediately indicate several methods that are clearly ineffective, although there is a lot of information on the network about them.
- Physical shutdown of ports. This, of course, is cool, but there are other ports and adapters for them. In addition, for some reason everyone forgets about the mouse, keyboard, speakers, etc.
- Removing USB drivers has zero effect. The system itself will offer to install them, either from the network or from the drive itself.
- Prohibition of flash drives in the group policy editor (just prohibit each new device by ID). It is better to prohibit everything, and allow the necessary ones, as I will show below.
I, perhaps, will start with the Group Policy Editor, since I consider this method the most convenient and effective among the rest of the system ones.
Blocking flash drives in the Group Policy Editor
We need to go to the GPO. Open a command prompt (type "cmd" in the search box, click right click mouse, run as administrator).
AT command line type gpedit.msc and press Enter.
The GPO window will open. Now let's move on to the section where the policies we need are configured - "Access to removable storage devices." Click on it - existing policies will appear on the right.
AT this case we are interested in policies related to removable media. However, here you can configure the work with discs (compact, DVD, floppy), tape drives and other devices.
Also, very conveniently, it is the ability to choose what exactly needs to be banned. For example, in order to save information, you can disable recording.
To do this, right-click on the relevant policy and select Edit.
Now select the "Enable" command and click "Apply".
When trying to copy any file to removable drive, the user will not be able to do this (unless they are a member of the Administrators group). He will see this message.
By the same principle, other functions (read, start) are applied.
There is also a policy that disables all device classes. That's what it's called.
Access only certain devices
The method above is the easiest. However, if you have only a few media that are used with your PC, then you can create a whitelist.
For this you need:
- know the device GUID
- apply two policies in GPO
Finding the GUID of a USB Drive
First, install the device in the USB port, then, using the command shown below, go to the "Device Manager" (well, or, as usual, through the "Control Panel").
Find your device under Portable devices and open its properties.
Go to the "Properties" tab, select the "GUID" property of the class from the list and copy its value.
Set up the required policies. Now let's move on to the GPO. Open the same directory as above - "System". But now go to "Device Installation - Device Installation Restriction".
In the list of policies, we need two selected ones. Just turn on the second one.
In the first one, you also set the GUID values of the devices that are allowed.
Copy the GUID value here (for the cursor to appear, click in the field 2 times).
Now only these devices will be able to start. If you insert other devices, they simply will not be visible.
NOTE. In addition to a policy with a global identifier (GUID), you can also use a policy with a regular one (ID). However, for some reason it did not work for me (I assume that because of the OS version). It works exactly on Windows 7 - I used it myself a few years ago.
Disable Flash Drives in the Windows Registry
The prohibition of the use of flash drives can also be done using Windows Registry. I would like to point out right away that this way only works when installed driver to USB. If you do everything described below when it is not yet installed, then when you connect any drive, you will be prompted to install this driver. And the value changed earlier will change back to the default settings.
This method works on all Windows OS. However, it is most relevant for Windows XP, since there is no Group Policy Editor. Therefore, the example will be shown in the environment of this system. So let's continue.
First, open the registry. At the command prompt, type "regedit" and press "Enter".
Now go to this registry branch:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\USBSTOR
As you can see, there are several options there. One of them is Start. It determines how the USB drive is available (for any operations, for reading, writing, etc.). On the this moment set to 3. If you change it to 4, the drives will become unavailable at all. This is what we need.
Click 2 times and change the value to 4.
Now, when connected, the device simply will not be displayed.
HEALTHY! On the admin forums, many write that the method does not work. However, this is not so. It's just that often they try to use it in the domain groups of computers in an organization. And there, as you can guess, the OS on all PCs is not updated: on some XP, on others seven, and on some even 2000. So, in these systems, some protocols and tools simply do not exist, as a result, the value on the admin computer, and after him and on everyone else, is reset to the standard.
How to disable USB ports in BIOS
Another way to disable the use of flash drives is to disable the USB ports in the BIOS. It is not difficult to do this. However, from my point of view, it is not effective enough. Although, given that most users have no idea not only that ports can be disabled there, but also about how to get there, then maybe this is a convenient and fast way.
Ban USB usage drives in many organizations is necessary to prevent two troubles - the removal of information (secret documents, etc.) and its entry: viruses, games, and the like. Therefore, it is not surprising that such applications are often received system administrator. It would seem that the task is solved simply - disable through the BIOS USB ports, but other USB devices such as a mouse, keyboard, printer, or phone charger will also be affected. So, it is necessary to programmatically prohibit the use of flash drives, while not hitting useful USB devices.
Disable USB Windows 7, 8, Vista
Beginning with Windows Vista a very useful hive has appeared in local group policies (gpedit.msc), located in Policy " local computer"\u003e Computer Configuration\u003e Administrative Templates\u003e System\u003e Access to Removable Storage Devices. It can be flexibly configured to prohibit reading, writing, and executing on various classes of removable devices. 
Disable USB Windows XP
To disable removable storage USB devices in Windows XP, you need to tweak the registry a little and adjust the permissions to the driver files:
- Disable USBSTOR service (regedit.exe) "Start"=dword:00000004
- Account SYSTEM set permission "Deny" for the following files:
- %SystemRoot%\Inf\Usbstor.pnf
- %SystemRoot%\Inf\Usbstor.inf
Batniki, for shutdown automation:
off-USB.bat
on-USB.bat
Disable USB via Group Policy.
A ready-made group policy for prohibiting drives appeared in server operating systems, starting with windows server 2008, you can configure them on the controller through the gpmc.msc snap-in, they are located on the same path (Policy> Computer configuration> Policies> Administrative Templates> System> Removable storage access). It works flawlessly, but it will be applied only to operating rooms. Windows systems Vista 7 and 8. 
Things are somewhat more complicated with Windows XP, despite Microsoft's announcement that XP will be discontinued in the spring of 2014, it still occupies a large part of the operating systems used in the corporate sector. It doesn't matter, we'll set it up just like the local one, but only through the GPO. Run gpmc.msc, create an object group policy and start editing it.
And the most important thing. In windows XP and server 2003, there is no Preferences section in the policy editor and therefore registry changes will not be applied. To add this section, you need to apply update KB943729 (Group Policy Preferences Client Extensions) on WinXP machines. By the way, after the update, the settings section is not visible to the local group policy snap-in, but registry changes through domain policies are applied perfectly!
Hi all! Today we will consider several questions at once on the topic of how to connect USB to a computer. First, we will learn how to connect any device to a PC or laptop. And secondly, I will tell you how you can connect to a computer additional USB ports if you don't have enough for all devices. So let's go!
How to connect a USB cable to a computer?
The USB port is by far the most common type of device connection to a computer or laptop. There are three data connectors - 1.0, 2.0 and 3.0. If the first one can now be found only on the oldest computers, then the second and third are used today. At their core, they differ in data transfer speed. And by appearance, which is more important for us now - color. USB 2.0 has a black connector and plug, USB 3.0 is blue. You can read more about the specifications and differences between the standards.
Before connecting USB wire to the computer, look at the plug of your gadget - if you connect the blue connector to the black port, then the device will not use all its speed characteristics to the maximum. If you stick a black fork into a blue one, then absolutely nothing will happen - just USB port 3.0 will work at the speed that is maximum for 2.0.
So let's look at back panel on your computer, find the USB port of the same color as the plug, and connect it.
After that, the device will either be determined by itself in the system, if it is a keyboard, mouse, webcam, or some other simple and common device for which Windows already has a driver. Or for work it will be necessary to install the software that is attached to the device on CD.
How to connect additional USB ports to a computer?
Any modern motherboard already has built-in USB ports - both 2.0 and 3.0. However, we usually connect so many different peripherals that they can easily be missing, for example, in order to connect a USB flash drive or external drive and upload fresh photos to it.
Connecting a USB bracket to the rear panel
What to do? There are two ways. The first, preferred one is to buy a separate bracket with USB ports and insert it into the additional slots on the back of the case - in the same ones where we attach the video or sound card, wireless adapter, and other components connected directly to the board. It looks like this:
In order to carry out this task, it is necessary that the motherboard supports connecting additional USB ports. This can be determined by the presence on the system board of connectors labeled USB or USB 3.
USB 3.0 connectors are large, have many pins and are designed to connect two ports at once in one plug.
USB 2.0 is smaller and each of them can be connected to 2 ports separately.
Accordingly, we look at the presence of such connectors on the motherboard, buy the appropriate brackets, fix them in the back of the case and connect them to our connectors.
Connecting a block with USB ports instead of a floppy
Another variation of this method of increasing the number of ports is a special block with USB, which is inserted in the front of the case instead of the old floppy drive - floppy 3.5
There are many options for this block. For example, combined for connecting USB 2.0 and 3.0
And in the following example, USB 2.0 ports are combined with microphone and headphone jacks
The connection of such a block occurs in exactly the same way as the bar described above - to the corresponding connectors on the motherboard.
External USB hub
Finally, another option to increase the number of ports is to buy an external USB hub. However, there are a number of disadvantages here, because of which I would not connect any serious equipment through it, but would use it only for flash drives or, in extreme cases, a mouse.
Since this is a hub, all the load from several of its ports goes to one single computer to which it is connected. Due to this overload, certain devices can periodically fall off, which is not good. If connected to USB hub HDD, then the electricity supplied through it may not be enough for its operation. Therefore, we leave this method only for light fast food - flash drives.
Thank you! Did not help