Email not working

After upgrading to Window 2000 from Windows/ME
I’m unable to open my POP3 email account.
I have setup Outlook 2000 & Outlook Express to access my bellsouth.net POP3 mail account, but it never comes back with my mail. I also went directly to the bellsouth.net site and entered my mail address & password still my mail never opens.
If I use any other computer I can get my mail either way.
Any help will be greatly appreciated. .

Gilc