PC A downloads pop3 with no probs on LAN Z.

PC B can't download pop3 from the same account on LAN Z.

PC B can download stuff from an exchange account. POP3 just hangs on downloading x message of 10 or something.

PC B got wiped, a fresh install of Windows 7 and Office 2010. Nothing else, no AV or anything.

PC B still can't DL pop3 mail.

It doesn't matter what user account you use to log in with, domain user or local. I've tried 2 different network points, WIFI and wired too.. tried alsorts but it still don't work.

PC A downloads from the same account, from the same network, behind the same router on the same cable with no issues at all.

Both are set to leave messages on the server btw ...any ideas?

Because omgwtfbbqWTF 

PC B mac address blocked from pop3 server?