The server only needs to understand ".net 2.0". When linq was added in .NET 3.0, the CLR was not updated. So far, everything has been compiled on a machine that, at least .NET 3.0 , will work fine.
It often seems that this web server does not support 3.0, because ASP parameters in IIS only provide you with parameters 1.0.3705, 1.1.4322 and 2.0.50727. But ".NET 3.5" still uses the CLR "2.0.50727".
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