Citrix printing to Workcentre 57xx and 75xx models causing "thunking spooler" errors. Google threads indicat problem not unique to Xerox. Sample error message follows:
Faulting application splwow64.exe, version 6.0.6001.18000, time stamp 0x4791a2b0, faulting module ntdll.dll, version 6.0.6002.18541, time stamp 0x4ec3e855, exception code 0xc0000374, fault offset 0x00000000000acb17, process id 0x50f8, application start time 0x01cd9502c4ea976a.
splwow54.exe process converts 32 bit to 64 bit dlls in a 64 bit spool driver stack upload. Error above points at the ntdll.dll in the Xerx driver.