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Short question
One of my flash drives is continually disconnecting and reconnecting on Windows XP. I plugged it in and for few seconds I can see a drive letter in "My Computer". After few seconds it disappears and then reappears.

How can I fix it?

Details
Flash drive works because it works on Linux on the same computer and works properly on another computer (with Windows XP too). Another flash drive works without any problem on that computer and Windows XP.

I tried removing drivers but it didn't work. After a reinstall the problem shows up again. In the USB Root Hub Properties I unchecked "Allow the computer to turn off this device to save power". It also didn't work.

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Have you tried using a different USB port? –  Tog Nov 5 '10 at 8:23
    
Yes but nothing has changed. It works on same usb port on another OS, and another flash drive works in same usb port on windows. –  Tomas Nov 5 '10 at 9:36
    
Sounds like a corrupted driver (e.g. tries to install, fails, uninstalls, then "refinds" the hardware, loop). Try running the sfc tool to scan the Windows system files to check for any corruptions, and report back. –  Breakthrough Feb 22 '11 at 21:27
    
Cant be sure that this will work but try this: run->devmgmt.msc->USB Root Hub properties -> Power management -> dont allow OS to turn of usb port. Can also try to disable USB legacy support in the BIOS –  aCuria Mar 4 '11 at 21:34
    
@Breakthrought Scan with sfc didn't find anything. (After scan it didn't show anything so I think that it didn't find...) –  Tomas Mar 11 '11 at 7:59

1 Answer 1

I've seen this problem a few times in recent years with various USB devices and NICs (Network Interface Cards). The solution was to perform a deep power cycle, which is done as follows:

  1. Shut down your computer (gracefully, using the Operating System's proper "shut down" procedure)
  2. After the computer is powered off, disconnect the AC power (if using a laptop, remove the battery too) and the video display and any other devices that have their own power supplies/sources
  3. Try to turn the computer on at least three times by pressing the power button
  4. Re-connect all devices and the AC power (if using a laptop, re-install the battery first)
  5. Turn the computer on and try to use your USB device again

Step number 3 is what qualifies this as a "deep power cycle" and it is essential with no power sources connected because it has the effect of draining capacitors and other electronic components in your computer that might be retaining an inappropriate [yet subtle] charge.

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I tried this but I didn't not success. I think that it it is not hardware error because flash disk works on the same computer but not same operation system. –  Tomas Mar 11 '11 at 8:01
    
You're right -- that definitely points to software. –  Randolf Richardson Mar 11 '11 at 15:35

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