When Outlook 2000 and 2002 users click on a hyperlink in an email message, they might receive the error message, "This operation has been cancelled due to restrictions in effect on this computer." You might guess that this message points to problems relating to the Outlook Email Security Update, but it's actually an Internet Explorer (IE) 6.0 problem. Microsoft Support Online explains how to repair the Windows registry to avoid the message.

http://support.microsoft.com/support/kb/articles/q310/0/49.asp