System.IO.FileNotFoundException: Could not load file or assembly 'file:///C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET

Hi @Matthew Ikechukwu,

First try running Visual Studio as an administrator. Just right-click the Visual Studio icon and click Run as Administrator.

If the error persists, try the following:

• Try performing a full solution build. If that doesn't work, click Build -> Clean Solutionand republish to the server.
• Close Visual Studio and stop the IIS website, then delete the temporary project files in the corresponding folders below:C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files
• If you are using performance testing, you will need to remove the assembly PostProcessor Type attribute in the system.web>compiler element in web.config.

    <system.web>
    <compilation debug="false" targetFramework="4.5.1"  
            assemblyPostProcessorType="Microsoft.VisualStudio.Enterprise.Common.AspPerformanceInstrumenter, Microsoft.VisualStudio.Enterprise.AspNetHelper, Version=12.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
    </system.web>
  

• If you use Visual Studio Performance Tools then it is possible that Visual Studio left a key in your web.config appsettings section. It causes a 32 bit library to load, which won't work if your application is loading in 64 bit mode. Check for the following and remove it:

    <add key="Microsoft.VisualStudio.Enterprise.AspNetHelper.VsInstrLocation" value="C:\Program Files (x86)\Microsoft Visual Studio 11.0\Team Tools\Performance Tools\vsinstr.exe"/>
  

Best regards,
Lan Huang

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