Configuration of Outlook’98

I have configured Outlook profile for a client, everything looks fine, when I double click Outlook, I get option to connect/work offline, I choose connect. At this point I see all the messages also, even new messages but when I double click a message, I get error as Network problems are preventing connection to the Exchange server computer”, using Outlook 98, Exchange 5.5. It’s just this one user on her laptop, I was able to cnfigure the same user’s profile on another laptop fine so I know itis something in the laptop, any suggestions?