URL Hyperlinks are shrouded

I'm using both Firefox 3.6.13 and Internet Explorer 8 on Windows XP SP3. I'm having difficulty getting to web pages from hyperlinks in emails, documents and some web pages. They seem to be shrouded and look like this (taken from a Windows Secrets newsletter):

http://windowssecrets.com/links/yl8...ls/?siteID=TnL5HPStwNw-pu2aQ__lnu0zMuc2y.n9dQ

The browser returns a message that it can't handle the URL. Anyone have any idea how to solve this problem??

 

Yes, I've tried copy and paste with the same result.

 

I just tried going to another computer running the same version of Windows and the links work in both Firefox and IE. That indicates that something on the computer is changing the links and making them unreadable. I'm going to do thorough virus and spyware scans but can anyone think of anything else I might try???