VS2017 Could not load file or assembly Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll or one of its dependencies

Question

When trying to open an older solution in VS2017 there is an old Unit Test project that is giving me a problem when building.

I keep getting the following error when building this test project:

Could not load file or assembly 'file:///C:\Projects\MyProj\Test\DAL\UnitTestProj\Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll' or one of its dependencies. The system cannot find the file specified.

I checked the project's references and it appears to be referencing Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll . Additionally there are no code errors. How could I ever figure out if it is one of its dependencies that it can't find?

Answer 1

I had a similar issue (with the additional message The "BuildShadowTask" task failed unexpectedly ) with a project originally developed with VS2010, and got to spend the last few hours learning about yet another legacy facet of the build process.

There is a good chance that you are dealing with private accessor files ( .accessor ), which were deprecated in VS2012 ( original source ). This was foreshadowed in an announcement from the VS2010 team that they were no longer working on these features.

There is also a chance you're just dealing with erroneous refs to the wrong version of UnitTestFramework, but a NuGet restore should fix this. If not, see this GitHub thread for a possible fix (manually change the ref to the public folder), or move to the new MSTest.TestAdapter and MSTest.TestFramework packages (see MSDN support thread ).

Solutions

A. Edit the unit test .csproj and change the item Include references from Shadow => None : <Shadow Include="Test References\\namespace.accessor" /> to
<None Include="Test References\\namespace.accessor" />

B. Better yet, simply delete all the .accessor files from the unit test project's Test References folder.

Ideally, you would also rewrite your unit tests to remove references to private methods, either by re-architecting to separate concerns or by changing properties to internal and using "friend" with the InternalsVisibleToAttribute .

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For those who need to continue supporting testing of private methods for some reason, the same post provides the following suggestions to the logical question "What is available for me then?" :

For those who wish to continue testing internal APIs, you have three options:

1. Use the Microsoft.VisualStudio.TestTools.UnitTesting.PrivateObject class to assist in accessing internal and private APIs in your code. This is found in the Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll assembly.
2. Create a reflection framework that would be able to reflect off your code to access internal or private APIs.
3. If the code you are trying to access is internal, you may be able to access your APIs using the InternalsVisibleToAttribute so your test code can have access to the internal APIs.

However, there is not any good replacement for Code Generation for the new features added by the lanugage teams. You may create the TestMethod stubs and then remove the internal code. You only need to keep the stub itself.

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Further reading / sources that helped me piece this together:

• VS 2005 ASP.NET explanation of accessors
• 2008 blog article explaining how to work around this for build servers
• MSDN forum thread with discussion on accessor purposes, implementations, and workarounds. Start about 1/3 down.
• MSDN BaseShadow docs
• MSDN PrivateObject class

Answer 2

Right click the project references folder. Add reference > Assemblies > extensions. Check Microsoft.VisualStudio.QualityTools.UnitTestFramework 10.1, and uncheck any older version.

Answer 3

This is related to Visual studio Enterprise 2015, add new load test was failing: and spiting as "Unable to find assembly 'Microsoft.VisualStudio.QualityTools.LoadTest, Version=14.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"

Due to Assembly installed in public assemblies shows as version 10.0.0.0 which is missed in GAC,

GAC had only 10.1.0.0. Once GAC updated with 10.0.0.0 and restart VS 2015. should resolve the issue similar to this.

Some more detail for better reasoning, System Assembly path and project path DLL path ......\\Program Files (x86)\\Microsoft Visual Studio 14.0\\Common7\\IDE\\PublicAssemblies\\Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll

.CSProj reference version

Answer 4

I had a same issue while I was upgrading project to.Net4.8 in Visual studio 2022 earlier we were using Visual studio 2017.

Error:
The "BuildShadowTask" task could not be loaded from the assembly ***\Microsoft.VisualStudio.TestTools.BuildShadowsTask.dll. Could not load file or assembly 'file:///***Microsoft.VisualStudio.TestTools.BuildShadowsTask.dll' or one of its dependencies.

Solution: I removed ".accessor" files from project as that is being used for accessing private methods(most probably accessor is depricated). Then we used "PrivateObject" class for accessing private members in UnitTest. Later we updated Unit Test case. Code references could be found from below articles.

Unit test private methods?

Unit Testing: Exposing Private Members

Answer 5

I had a similar issue (compile project in server Jenkins)

Solution: Include VS.QualityTools.UnitTestFramework to reference project, whit Pakage Manager: PM>NuGet\Install-Package VS.QualityTools.UnitTestFramework -Version 15.0.27323.2 https://www.nuget.org/packages/VS.QualityTools.UnitTestFramework

Answer 6

Try to fully uninstall Visual Studio 2017 (not repair) . Then download the latest version and install it. Remember to check if MSBuild is added to installation files. Remember to delete folder inside Documents: Documents\\Visual Studio 2017 . In my case, this simple solution fixed all errors.