Windows7 stops the print spooler and then it appears no printers installed

Windows7 stops the print spooler and then it appears that there are no printers installed. When I restart the print spooler in services, all to the network printers reappear in Devices and Printers. When I try to print, the drivers disappear and MS Office says no printers are installed. After some time with the print spooler running, something stops it again.