Default desktop icons stop functioning

Here is the problem, There are three Windows 2000 Servers, they have been running fine then one day wham the desktop icons when used report that the path is not found or some non sense like that. I am talking about the default icons like My Computer, Recycle bin etc.. This has happened to all three of these servers on seperate occasions. The start button still functions as do all other aspects of the server. There are user connections ect. everything is ok except these damn icons. If anyone hasany info that could help me resolve this that would be great. The only wayIhavefound to restore these is to reboot, Logging off and back on as another user does not help.

Thanks
Hugh Brown
hbrown@alphanetsolutions.com