Unable to download new messages in Outlook 2003

For a while I have been getting error message:
Task 'pop.att.yahoo.com - Receiving' reported error (0x800CCC0F) : 'The connection to the server was interrupted. If this problem continues, contact your server administrator or Internet service provider (ISP).' which I was able to correct if I checked my settings in the tools menu, but recently nothing will allow me to correct this problem.

I have the original MS Office Student and Teacher Edition which would start by itself when I put it in the CD drive. Tonight I could not get it to start automatically and "correct errors," nor could I find the right "Setup" file to start manually.

I would appreciate any suggestions on how to get Outlook 2003 working again. Thanks in advance for your help.

SRL