Win9x PCs lose printer folder contents.

Win9x clients have local and network printers installed and visible in the Printers folder. Perodically, the user can’t print and an examination of the Printers folder shows it is empty; not even the local printer is there! A reboot restores the contents and the ability to print. Affecting several PCs but not all of them on the network. (Network is small LAN, no subnets).