I think that your PC is referring to your DRIVES not drivers. The Operating System (Windows?) is running out of space on yoyur hard drive(s) in which to work.
So you need to make some more space for it. You can either delete some old data that you don't need anymore or use the remove Programs Utility to remove old programs that you don't use anymore or install a second hard disk and move some of your data on to it.
When have done any of the above, then defragment your Hard Disk Drive.
t
July 2008