System.IO.FileLoadException: Could not load file or assembly ‘System.Diagnostics.DiagnosticSource, Version=4.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’ or one of its dependencies. The located assembly’s manifest definition does not match the assembly reference.

Posted on March 1, 2017 in .NET, ASP.NET

Solution:-

If you use .NET Core tools preview 2 (e.g., VS2015 Update 3), then everything works fine on both .NET Framework 4.5.1 and 4.6.1.
If you use .NET Core tools preview 3 (e.g., VS2017RC), then it works fine on .NET Framework 4.5.1, but fails with the error you posted on .NET Framework 4.6.1.
The issue isn’t specific to NodeServices. You can repro the same error just by trying to use System.Net.Http.HttpClient (and NodeServices triggers it precisely because it uses HttpClient internally).

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