suddenly getting access denied vista pc other pcs

suddenly i stopped being able to access my shared C drive from other pcs on my LAN. I can see out and move files around "from" the vista machine, but other computers cannot do this EXCEPT to the My Documents folder which I shared manually after the problem began).
More seriously, I cannot get printer information. The Vista machine claims the network spooler is not running on my print server but no other computer has a problem printing to it, and prior to this bug, i WAS able to print from vista to the networked printers. -- Al K (The Spook In The Machine)