IPP problem

[ktmrandy]

I have a problem with IPP printing. I have tried printing on one xp pro machine and one xp home machine but I cannot print to a printer behind a firewall using port forwarding across the internet. The printer is a xerox phaser 860DP. The Xerox guys can print to it using an xp pro and  a win 2000 machine. I have compared all my computer settings to the computer the xerox guys are using. They match as far as we can tell. The xerox guys have no further help for me. The installation proceedure shows I can connect to the printer and install the drivers. It even shows the pages the Xerox guys have printed. When I attempt to print a test page I get the message that exploers will have to close. Does anyone here have any ideas?