Whether you are hooking up a USB flash drive, headset, printer, or even your smartphone, you expect your USB devices to just work when you plug them in. That’s the beauty and simplicity of USB. It is designed to allow devices to be connected and disconnected at will, often to both Windows and Mac computers, without a whole lot of hassle. When your USB port suddenly not working, the problem can always be tracked down to either a hardware or software failure. Some of these problems are the same across both Windows and Mac, while others are unique to just one or the other.
What is USB Port?
A USB port is a standard cable connection interface for personal computers and consumer electronics devices. USB stands for Universal Serial Bus, an industry standard for short-distance digital data communications. USB ports allow USB devices to be connected to each other with and transfer digital data over USB cables. They can also supply electric power across the cable to devices that need it.
Both wired and wireless versions of the USB standard exist, although only the wired version involves USB ports and cables.
Steps to Try When Your USB Port not Working
Here are eight things to try when your USB port not working:
1. USB Port Not Working? Give a Physical Examination.
Before proceeding, note that you’ll need to be sure that it is the USB port that is faulty and is not working, rather than the device you’re connecting.
To establish which is the problem, connect the device to another USB port. If it works, then the problem is the first port; but if the device remains undetected, then you have a faulty device. If you can’t reformat the USB drive, it will need replacing.
If there’s a problem with your USB port, you’ll notice it thanks to either of these things:
- The device fails to be detected
- Your operating system displays an error message relating to the device (removing and replacing the device might solve this)
Either way, you should investigate the state of the USB port. Has it been damaged in any way? The safest way to find out your USB port is not working is to shut down your PC or laptop.
Next, look at the USB port. Is it clean and dust free? If you’re using a desktop, or the USB port is at the back of a PC tower, there’s a chance that dirt, dust, and general detritus might have become embedded in the port.
Dust will reduce airflow, causing your system to overheat. It is particularly damaging to laptops, where overheating can reduce performance in seconds. Clean out the drive with a can of compressed air. A vacuum cleaner might also prove handy here.
Finally, grab a USB cable (or flash drive, whatever) and gently wiggle it around. If the drive is moving and feels loose—typically this will be up and down—then you have a problem.
2. Restart Your Computer

Sometimes you get lucky, and the easiest solution ends up fixing the biggest of problems. And when the problem is USB port not working, the easiest fix is to restart your computer, or simply turn it off and then turn it back on again.
When the computer has finished restarting, go ahead and plug in your USB device. If it works, that means the problem has sorted itself out, and you don’t need to worry about it.
A lot of things get refreshed under the hood when you restart a computer, which can actually fix a whole lot of different problems.
If you aren’t that lucky, then you’ll want to move on to more complicated fixes.
3. Physically Inspect the USB Port

USB is pretty robust, but the fact is that these ports are wide open whenever you don’t have a device plugged in. That means it’s pretty easy for debris, like dust or food, to get wedged inside.
So before you do anything else, take a close look at your USB port. If you see anything stuck inside, you’ll want to shut your computer down and gently remove the obstruction with a thin plastic or wooden implement like a toothpick.
In some cases, a product like canned air can be useful in blowing obstructions out of a USB port. Just be careful not to shove the obstruction further in.
USB ports can also fail due to a loose or broken internal connection. One way to test this is to insert your USB device and then gently wiggle the connection. If it briefly connects and disconnects, then there is a physical problem with either the cable or the USB port.
If you feel a great deal of movement when you gently wiggle the USB connector, that indicates it may be bent or broken off the board that it’s supposed to be connected to. And while it is sometimes possible to fix this type of problem, you may be better off taking it to a professional.
4. Check Device Manager on Windows 10

Begin by right-clicking on the Start menu and selecting Device Manager.
The Device Manager lists the devices attached to your computer, grouped into categories. It’s arranged alphabetically, so you should find Universal Serial Bus controllers towards the end of the list.
Expand the list, and look for the USB Host Controller. The device you’re trying to find may have a longer title, but it will feature those three words.
No USB Host Controller? This may explain why your USB device doesn’t work. To fix this, click on the Scan for hardware changes button on the toolbar. This will commence a check of all connected hardware, and in most cases will detect the USB port and anything connected to it.
If this still hasn’t worked, it’s worth taking the time to reinstall the USB Host Controllers. Right click on the USB Host Controller items in turn, and select Uninstall on each. Wait while they’re uninstalled, then reboot your computer.
As Windows restarts, the USB Host Controllers will be automatically reinstalled. This “refresh” can help to fix problems with the USB port.
Note
If you’re using a USB mouse or one with a USB receiver, it will be disabled while the USB Host Controllers are uninstalled.
If you are also interested in learning how to fix Windows 10 Wi-Fi problem, why not read our article about it.
5. Try Plugging Into a Different USB Port

If restarting didn’t help and USB port still not working, and it looks okay physically, then you should figure out whether you’re dealing with a port, cable or device failure.
Most computers have more than one USB port. So a good way to rule out a single broken port is to want to unplug your USB device and try it in a different port.
If your device starts working when plugged into a different port, then the first port probably has a physical problem that needs to be fixed if you want to ever rely on it again.
6. Reset the System Management Controller (Mac)
If you have a Mac, then resetting the system management controller (SMC) may fix the USB not working problem. This can be accomplished through the following steps:
Resetting the SMC for Macs
- Shut down the computer
- Plug in the power adapter
- Press and hold shift + control + option and then press the power button.
- Release the keys and power button all at the same time.
- When the Mac starts back up, the SMC will have reset.
- Check to see if your USB device works.
Resetting the SMC for iMac, Mac Pro, and Mac Mini
- First you should shut down the computer.
- Then unplug the power adapter.
- Now you should press the power button and hold it for at least five seconds.
- After that release the power button.
- Reconnect the power adapter and start the computer.
- Now you should check to see if your USB device works.
7. Update Your System
Although less likely, there is a chance that updating your system could solve your USB port problems. This process is different depending on whether you’re using Windows or OSX.
On a Windows computer:
- Right-click Start then left-click Run
- Type devmgmt.msc and click OK, which will open Device Manager
- Locate Universal Serial Bus Controllers in the list
- Click the arrow next to the little USB cable so that it points down instead of to the right
- Right click on the first USB controller in the list.
- Left click on update driver.
- Select search automatically for updated driver software.
- Repeat steps 5-7 for each USB controller in the list.
- Restart your computer and check to see if your USB device works.
On a Mac:
- First you need to open the app store.
- Then click Updates on the toolbar.
- If any updates are available, click on update or update all.
- Restart your computer and check to see if your USB device works.
8. Try Plugging in a Different USB Device
If you don’t have a spare computer, but you do have an extra flash drive laying around, or any other USB device, then try plugging that in before you move on to anything more complicated.
If your other device works just fine, then you’ll know that your ports are in good working order. In this case, you may need to fix or replace the device that failed to connect.
If your USB ports still don’t work after restarting and trying different combinations of devices, cables, and computers, additional steps to fix the problem are more complicated and specific to either Windows or Mac.
9. Swap to a Different USB Cable
USB cable failures are more common than USB port failures, so make sure to swap in a different cable if you have one handy. If your device suddenly starts working, then you know that the problem was a broken wire inside the other cable.
10. Plug Your Device Into a Different Computer
If you have another computer or laptop handy, then try plugging your USB device into it. This is an easy way to rule out a problem with the device itself.
If your USB device springs to life the moment you plug it into your backup computer, then you know for sure that you’re dealing with a USB port problem.
You’ve Fixed Your Broken USB Port!
As you can see, you have several options for repairing USB port not working problem. In most cases, it won’t be dead, and you’ll be able to fix it. Remember, when your USB port is not working, you need to:
- Make a physical check
- If necessary, make a physical repair to the port
- Reboot Windows
- Check the Device Manager, uninstall the USB Host Controller
- Disable USB Selective Suspend power saving option
USB ports aren’t the only potential weak spots on your computer. Looking after your hardware will reduce potential failures, and you can save a lot of money if you know how to test your PC for failing hardware.