Though they did at first, hyperlinks to web pages no longer work in my Excel
worksheets (Office 2003). I can create them, but when I click on the
hyperlink I get an error message that says:

"Unable to open http://www.google.com/. Cannot locate the internet server or
proxy server."

But hyperlinks do work in all of my other MS Office applications (Word,
Access, PowerPoint).

Does anyone have any idea what might be going on here?