I am trying to connect my Mac clients to our Windows Server printing system with IPP. I've had several problems along the way to this point, especially that Windows IPP doesn't automatically listen on port 631. On my Mac client (OSX 10.6.3), I've been using CUPSadmin at
to do the installation of the http port 80 printers.

I have encountered a situation though where no matter what I try, either with
(port 631, which I've opened on my server and bound IIS to in addition to port 80) or
When I try to print to a printer using http port 80 or ipp port 631 or 80, my Mac CUPS queue will initially report the warning message:

Printer does not support IPP/1.1, trying IPP/1.0...
, then blinks by and the printer on the Mac then goes to a paused state. Further investigation into the CUPS error_log reveals this:

printer-state-message="Unable to get job 33 attributes (Client: (404) Not Possible)!"
The interesting thing is that the Mac client will end up having the document remain in its local queue and the local printer queue will be paused, but the document successfully does get sent to the Windows print server and will get printed out immediately. It appears that the Mac CUPS system isn't getting the "printed successfully" information for the job and it stops.

My environment consists of Mac 10.6.3 clients, Windows Server 2008 SP2 printer that does SMB,LPD, and IPP via IIS. Everyone is on the same network and I've opened up all firewall ports between my test clients and my server. My printers are networked and shared from the Windows Server, and have been in production for over a year. I am in a position where I need to offer printer queue access for our wireless users on their personal computers, and I would prefer to only open up port 80 instead of 515 and 80 (LPD and IPP clients).

I've done a packet capture of a working XP machine and also on the troublesome Mac, and so far I can't see much of a difference except that the Windows client has an extra couple HTTP/1.1 200 OK packets at the end that the Mac does not.