Best Products Computer Components What to Do When Your USB Ports Aren't Working Try these fixes on your PC or Mac by Jeremy Laukkonen Writer Jeremy Laukkonen is tech writer and the creator of a popular blog and video game startup. He also ghostwrites articles for numerous major trade publications. our editorial process Facebook Twitter LinkedIn Jeremy Laukkonen Updated on September 11, 2020 reviewed by Jon Fisher Lifewire Tech Review Board Member Jonathan Fisher is a CompTIA certified technologist with more than 6 years' experience writing for publications like TechNorms and Help Desk Geek. our review board Article reviewed on Feb 10, 2020 Jon Fisher Computer Components USB/USB-C Monitors Keyboards Mice Cards CPU Storage Laptop Bags & Backpacks Printers View More Tweet Share Email Whether you’re hooking up a USB flash drive, headset, printer, trying to sync your MP3 player, 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, or universal serial bus, which 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. Lifewire / Jie En Lee How to Fix USB Port Issues When your USB ports suddenly stop 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. Restart your computer. Sometimes you get lucky, and the easiest solution ends up fixing the biggest of problems. If restarting doesn't do the trick, then you'll want to move on to more complicated fixes. Why Restarting Something Tends to Fix Most Problems Look for debris in the USB port. These ports are wide open whenever you don't have a device plugged in so it's easy for debris, like dust or food, to get wedged inside. If you see anything stuck inside, 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. Check for loose or broken internal connections. 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. And while it is sometimes possible to fix this type of problem, you're probably better off taking it to a professional. Try a different USB port. Many computers have more than one USB port, so a good way to rule out a single broken port is to unplug your USB device and try it in different ports. Plug the USB device into a few of the ports on both the front and back of your computer. If the device doesn't work in any of the ports, there's likely a problem with its hardware. If your device starts working when plugged into different ports, then the first port probably has a physical problem that needs to be fixed. It's also possible that there's a connection problem with all of the USB ports on the front or the back, which is why it's important to try more than one on both sides. 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. 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. 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. Check the device manager (Windows). There are two things you can do with the device manager in Windows to get USB ports working again. Scan for hardware changes by right-clicking the name of your computer, and then clicking on scan for hardware changes. When the scan to complete and then check your USB device to see if it works. Another option is to disable and re-enable the USB controller. In the device manager, 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 and select Uninstall device. Repeat for each USB controller you find. Turn your computer off and then back on again. Windows will automatically reinstall the USB controllers, so check to see if your device works. Some of the steps may be slightly different depending on your version of Windows, but these work on Windows 10. Reset the System Management Controller (Mac). If you have a Mac, then resetting the system management controller (SMC) may fix your problem. These instructions do not apply if the Mac has the Apple T2 Security Chip. Resetting the SMC for Macs Shut down the computerPlug in the power adapterPress and hold shift+control+option and then press the power button.Hold all four keys down for 10 seconds.Release the keys and power button all at the same time.Press the power button to turn on your Mac.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 Shut down the computerUnplug the power adapter.Press the power button and hold it for at least five seconds.Release the power button.Reconnect the power adapter and start the computer.Check to see if your USB device works. 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 updating Windows or macOS. To update macOS on Mojave and later, click the Apple icon at the top left, and choose System Preferences > Software Update. Click Update Now if there's one available. On macOS on High Sierra and earlier, open the app store. 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.