Fix error 0x000006D9 on Windows 7 and Server 2008 R2 - Sharing Printer
If you are trying to share a printer on Windows 7 or Server 2008 R2, you may experience this error:
This issue occurs because the Spooler services uses the Firewallapi.dll file to make an API call to check the availability of the Windows Firewall service. If you experience this error, you must have the firewall enabled in order to share out the printer. This only seems to affect network printers, not locally attached printers.
To enable the firewall:
Start > Run > firewall.cpl > Turn Windows Firewall on or off > Turn on Firewall for the type of network location you use
As far as I can tell, you can turn the firewall back off after you share the printer and it will not mess up the printer sharing.