This is a known issue. The fix is here:
Windows Mail - MailTo link error
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Gary VanderMolen [MS MVP-WLM]
"canadian" <theolong@xxxxxx> wrote in message news:OsdSHqrBIHA.1356@xxxxxx
> Every time I try to go to an e mail address that is posted on an incoming e
> mail . I get his message, not once but 20 or 30 times all over my screen.
> The only way to get rid of it is to go to each window and close them one by
> one. Does anyone else have this problem. I have a new Toshiba laptop with
> Vista.
>
> Bernadette