"Cache" is the area of memory that "swaps" data from what is in use to what is in storage.If it is full or near full you will get error notifications. If you have not had this problem in the past, shut down all nonessential programs to free up some space. Rebooting will also help. I use ccleaner from www.ccleaner.com to clean my trash on boot.
Edited by gunner, 02 September 2005 - 11:19 PM.
Spike's advice: Backup your data routinely.