Connection Problem....

[USVAF_692]

Hello everyone,
      I have been having a problem with connection to servers via FS2004. I can connect then it is like 30sec. later i get the boot. I have my router port 80 and my Norton internet security port 80 enabled. I am using SBC yahoo DSL, with windows 2000. Once again, I log into a server and it allows me to stay connected, when someone logs in I get kicked, its weird, so if anyone could help that would be great.
USVAF_692