Read about the breaking changes ASP.NET 2.0 applications may encounter when running on IIS7 in Windows Vista SP1 / Windows Server 2008: http://mvolo.com/blogs/serverside/archive/2007/12/08/IIS-7.0-Breaking-Changes-ASP.NET-2.0-applications-Integrated-mode.aspx.
You can read about the recommended workarounds for there as well.
Thanks,
Mike Volodarsky
Program Manager
IIS Core Server
Learn more about IIS 7.0 and ASP.NET at http://mvolo.com
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