Cannot resolve Exchange mailbox name

I am setting up the last of 3 new Dell Latitude notebooks (Win2K Pro) and can't get Outlook 2000 to run on this third laptop (the first 2 worked just fine). When I try to configure Outlook for Corporate Mail and set up MS Exchange Server info service and "check mailbox name" it freezes. CTRL-ALT-DEL shows nothing running, and when I close Task Manager, I get an error that the rundll32.exe is not responding. I can connect to anything on our Win2K Server LAN, can reach the Internet, can see ourExchange server in Net Neighborhood, can run any of the other Office 2000 programs. I have installed all Windows and Office updates from MS -- no luck. Then I wiped the hdd and reinstalled everything fresh & tried running Outlook without any MS updates -- no luck.