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The "U" in USB stands for "Universal", and no other I/O port does so much for so many computer users as USB. From providing a home for keyboards and mice to driving printers, scanners, all-in-one units, and providing access to terabytes of storage and the Internet, USB ports do it all. That also means that USB-related problems can cripple your PC, leaving it unable to access storage, input, and output devices.
Tracking down the causes of USB-related woes can be difficult, but in this article, we show you the common and uncommon causes for USB problems – and their solutions.
Recent operating systems include drivers for common USB devices, such as keyboards, mice, and storage devices. If one of these devices is not recognized when you plug it into a USB port, try another USB port on the computer itself (we'll discuss troubleshooting ports built into hubs later), preferably a USB port built into the port cluster on the rear of a desktop PC.
If the device works in some USB ports, but not others, note the ports that are not working. This information will be used to help determine if the cause is the hardware setup at the BIOS level or at the Windows driver or Device Manager level.
If the device works on another PC, but not on yours, the problem lies with your PC. However, if the device doesn't work on any PC, it's time to replace the cable, or the device itself.
Even if you never have a USB device that doesn't work at all, you might see one of the following messages when you plug a USB device into your computer or into an external hub:
"This device can perform faster"
To solve this problem, we need to see how USB ports are configured in the system BIOS – and find out what type of USB hub is in use.
"Hub power exceeded"
This problem, on the other hand, requires a trip to the Windows Device Manager.
BIOS setup is the place to check if you have any of the following USB problems:
- Your system doesn't recognize a mainstream USB device, such as a printer, mouse, or storage device, in any USB port.
- You get a "This device can perform faster" error message when you plug a Hi-Speed USB (aka USB 2.0) device into any port on a recent computer.
- You can use a USB drive for storage, but you can't boot from it, and you've verified the drive is a bootable device.
- You can use a USB keyboard in Windows, but not for accessing the BIOS at system startup.
To check BIOS settings, restart your computer and press the appropriate key to open the BIOS setup menu.
Tip: If you are unable to access the BIOS setup menu with a USB keyboard, plug in a PS/2 (6-pin DIN) keyboard (if your system has a PS/2 keyboard port). It's worthwhile keeping an old PS/2 keyboard around for troubleshooting. Some USB keyboards can also be adapted to PS/2.
Once you have the BIOS settings menu open, what's next? Typically, you will find USB port settings in the Integrated Ports or Integrated Peripherals menu:
If the USB controller or host controller is disabled, no USB ports will be recognized by Windows, and consequently no USB devices will be recognized either.
What if some USB ports are usable, but others are not? Some systems enable you to specify the number of USB ports in BIOS setup.
To solve problems with "missing" USB ports, make sure the following settings are enabled:
USB controller
USB 2.0 controller (aka USB EHCI controller)
USB legacy support
Save changes, exit BIOS setup, and your system will restart, providing access to USB ports.
Tip: If you are unable to use a USB keyboard in BIOS setup, but it works after Windows boots, there's a problem with USB keyboard or legacy support. Change the setting, or contact your system or motherboard vendor for a BIOS update.
Comments are closed on this article
plzhelpme7
May 14, 2010 at 4:02pm
i still need help with my mp3 its getting a charge but its not conneting so im like wtf
Marcus_Soperus
November 18, 2009 at 3:36pm
My bad. I meant to write "self-powered generic hubs." Many (but not all) USB root hubs (aka onboard USB ports)which are self-powered because they are powered by the system power supply can temporarily provide more than 500mA to help spin up portable (bus-powered) hard disks. If your system's USB ports lack oomph, that's the time to use a double-headed USB cable to pull power from two ports.
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It's amazing how illogical a business built on binary logic can be.
m1k3_flrs
November 18, 2009 at 2:43pm
m1k3 very helpful article no doubt but how can you tell if theres a usb 2.0 in your system. my laptop reports 2 but it doesn't map which ones are. it only has 3 usb ports but all 3 are labeled with the normal usb icon.
Marcus_Soperus
November 18, 2009 at 3:38pm
If your laptop lists an Enhanced USB controller in Device Manager (see the figure on page 3 of the article), you have USB 2.0 support.
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It's amazing how illogical a business built on binary logic can be.
qz33
November 18, 2009 at 2:03pm
You said:
Some onboard USB ports are capable of proving more current to spin up these drives, while others are not. Keep in mind that self-powered hubs typically cannot provide additional power for these drives.
But maybe perhaps you meant:
bus-powered ?????
Is there any way to figure out which ports map to which entries in device manager?
heronhaus
November 18, 2009 at 1:40pm
Excellent article! It really takes a lot of the mystery out of USB problems.
