I'm having a problem getting iPrint direct to work in a couple of remote
sites, and am hoping that someone can shed some light on this issue.

I have a server located in Site A that acts as a ZENworks and iPrint server
for three remote sites: Sites B, C, and D. All sites are within a 15 mile
radius from where the server sits.

When all of the printers configured on the server are setup as iPrint
Direct, the printers physically located in Sites B and C start to have
problems: listed as unavailable or stuck in "Opening." The problems usually
appear when a user tries to print from Outlook or an Access database located
on another server. The user tries to print, the server goes out to lunch,
and no one else can print to that server. These printers work fine if
configured as a standard iPrint printer object.

These very same users, however, have no problems printing to the iPrint
Direct printers located at Site D. Same server, same workstation, same model
printer, different physical location.

I'm wondering if there is some sort of firewall issue. What sort of IP
traffic needs to flow to and from the server for iPrint and iPrint Direct?
What changes when a printer is changed from standard iPrint to iPrint