Vista can't detect or install usb pen drives

Hello,
I installed vista ultimate SP1 and everything worked well for a week or so. Then I did
a disk cleanup and selected all of the options. after that every new device I
add to the system even usb memory and usb harddrives cannot automaticaly find
drivers when I install them. instead i have to manually point the driver
search at the c:\windows directory and then it finds the drivers. I think I
removed the driver cache. Is there a way to restore the driver cache?