Error Message Outlook (Office) 2003

I am having a problem with Outlook 2003. When I click on a (web) link in a
message in Outlook 2003, I get the following error message and cannot connect
with the link:

Microsoftoffice Excel Viewer 2003
Command line option syntax error
Type Command /? for help

What do I do? Where do I type command /? for help?

Thanks for any suggestions you can make