All USB ports not working Windows XP

I am having a similar issue.  All USB ports are disfunctional with the exception of the two on my monitor, of which the monitor is plugged into a port on the back of my machine.  It's a Dell XPS 400 and it has NO OTHER mechanism for running a keyboard or mouse except for USB -- hence why uninstalling/reinstalling isn't really a viable option because once things are uninstalled, I have no keyboard or mouse.

Updated BIOS, chipset drivers, powered off things, even jumpered the CMOS -- nada.  And I know it's Windows XP because even with the ports working on my monitor, they will on occasion suddenly stop working...no power to the devices.

I know the ports are good as they work via the BIOS.  And here is the REALLY weird part -- if I plug in a flash drive in a port and reboot the machine, when it boots back up, it sees the flash drive.  However, if I remove it and then plug it back in -- nope...not recognized.

People all over are having this issue, but nobody is coming up with a solution.  It seems sad to see people tossing their computers when it's got to be a Windows issue...there is power going to these ports, but the OS does not recognize them, even though the device manager says everything is okee dokee.

HELP

Before you try anything else shut the computer down and disconnect the power cord, then, obviously, reconnect it and restart the computer.  For whatever reason, this will sometimes "reset" the motherboard's electrics and restart the power to the USB ports.

I have had the exact same problem with my usb ports. When it happened to my computer we had recently had a virus removed from the computer through the Microsoft Security Essentials program. A USB mouse was plugged in as well as a 2GB flash drive that was nearly full. I had an ipod USB connector plugged into a port but the ipod was not attached at the time. But as soon as I plugged in the ipod all of the USB ports refused to work. As handiman said above, the ports provide power but will not detect devices. For example, I can plug in an ipod and it will charge but the computer will not detect the ipod, and in itunes I have set it up so that it will open whenever the ipod is plugged in.

this helped... thank you.

Did what 'Jodido47' said, work?

 I would have suggested to go into MB bios and make sure that USB support was "enabled"

 Or reload USB drivers from the MB driver CD.

  But I was just wondering if his trick worked.

I have had the exact same problem with my usb ports. When it happened to my computer we had recently had a virus removed from the computer through the Microsoft Security Essentials program. A USB mouse was plugged in as well as a 2GB flash drive that was nearly full. I had an ipod USB connector plugged into a port but the ipod was not attached at the time. But as soon as I plugged in the ipod all of the USB ports refused to work. As handiman said above, the ports provide power but will not detect devices. For example, I can plug in an ipod and it will charge but the computer will not detect the ipod, and in itunes I have set it up so that it will open whenever the ipod is plugged in.

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Just wondering if you tried removing and reinstalling all USB controllers?

Volunteer J - MS-MVP - Digital Media Experience - Notice_This is not tech support_I am a volunteer - Solutions that work for me may not work for you - ***Proceed at your own risk***