Access outside email from groupwise 5.5

I am in the process of setting up groupwise 5.5 on win98/NT/2000 machines, I have gone through everything that I can think of to link to the outside account, we can talk to each other internally but cannot get mail from our ISP.

What am I doing wrong. Our network support has quit us I guess, neither one ever return my call. I guess maybe they think I should know more than I do??