HTTP/1.1 500 Server Error

Fixed it, also configured IIS 5.1 on my Win XP pro. Getting http://localhost home page I created on c:\inetpub\wwwroot\default.htm

But when I try to create the same project, I get

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Microsoft Development Environment
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The Web server reported the following error when attempting to create or open the Web project located at the following URL: 'http://localhost/WebService1'. 'HTTP/1.1 500 Server Error'.
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OK Help
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Still trying to fix it.