Internet Explorer & URL problem

A friend is running 2 Gateway computers from one cable moden using a
wireless router. Both are running windows xp and internet explorer.
When reading an e-mail with a url included and that url is clicked on
the linked site will open for a few seconds and then it will disappear
and the e-mail message will be on the screen. This happens only part of
the time on only one computer. Anyone ever hear of this?


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Ted1391