Exception from HRESULT: 0x80070057 (E_INVALIDARG)

Clear out the temporary framework files for your project in:

For Windows 7, the path is:

C:\Users\[username]\AppData\Local\Temp\Temporary ASP.NET Files\

For 64 bit systems with ‘Framework’ in the path the full path is:

C:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\

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