USB problems are legendary so nothing sounds amiss there. It is possible for USB ports to get blown by using those USB powered drives. Not supposed to blow out but it can happen.
Let's test those ports. How? I use a bootable LIVE CD of Linux. I don't have to know Linux, I don't install Linux. I just boot it and can see if the mouse and keyboard works or not.
This lets me see if this is a software or hardware issue.
More at http://www.howtogeek.com/howto/windows-vista/use-ubuntu-live-cd-to-backup-files-from-your-dead-windows-computer/
Bob
I am using a Dell Studio XPS 435MT running Windows Vista. A bit of background first. I had been having some problems with some external usb drives not being recognized, so I would go into the device manager and uninstall the drives, restart the computer, and the drives would then show up and work just fine until the computer was shut down. I would go through this cycle every so often and everything would work fine, albeit with the long run around of uninstalling and restarting. Yesterday though, upon starting the computer in the morning, my wireless mouse and keyboard would not work on the Vista login. The pointer was there, but neither the mouse or keyboard would make it move. I replaced the batteries in both and still nothing. Restarted in safe mode and nothing. I can get into the system recovery and use the mouse and keyboard, but upon doing both startup repairs and system restores, the mouse and keyboard STILL won't work on the login page. I read about using the command prompt devmgmt.msc, but when trying that I get an error that reads, "'devmgmt.msc' is not recognized as an internal or external command, operable program or batch file." Any suggestions on what to do? Many thanks!!!

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