http://support.microsoft.com/?kbid=308997

It looks like you followed that article to a letter. However, do each client have separate user names for accessing Outlook?

For example, you can choose to use another system variable name if you have a separate user name for Outlook access
Here's another article of worth:

http://support.microsoft.com/default...b;en-us;307868

What is odd is that it worked on one computer. Is there anything different about the one computer from the rest?