I recently booted my MacBook Pro via BootCamp to Windows 7 and discovered my printers mysteriously disappeared. Upon poking around, I got the following error message:
Windows can't open Add Printer.
Operation could not be completed (error 0x000006be).
I had also recently installed VMWare Fusion 3, and created a virtual machine to point to my BootCamp partition. After snooping around some more, I discovered this was causing my print nightmares.
Solution
Remove the following registry key and reboot!
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print\Monitors\ThinPrint Print Port Monitor for VMWare]
67d4c608-a84f-4234-9b21-dcf72fa24d04|1|5.0