Problem: When printing from Windows 7 to a shared printer, a "Local Downlevel Document" appears in the print queue and nothing is printed.
Resolution: First try restarting the print server (whatever Windows machine is sharing the printer for others to use). If that doesn't work, on the client, open regedit and go to HKLM\Software\Policies\Microsoft\Windows NT. Create a key named Printers, then inside that create a DWORD value called EnabledProtocols. Set the value to 6 and restart the computer.