title: System.IO.FileLoadException: Could not load file or assembly 'testhost, when debugging tests
body: <p>Everytime I try to debug unit tests from Rider IDE, test execution fails with an exception</p>
  
  <blockquote>
    <p>System.IO.FileLoadException: Could not load file or assembly
    'testhost, Culture=neutral, PublicKeyToken=null'. Could not find or
    load a specific file. (Exception from HRESULT: 0x80131621) File name:
    'testhost, Culture=neutral, PublicKeyToken=null'</p>
  </blockquote>
  
  <p>StackTrace:</p>
  
  <pre><code>at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, RuntimeAssembly locationHint, StackCrawlMark&amp; stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, IntPtr ptrLoadContextBinder)
  at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, RuntimeAssembly reqAssembly, StackCrawlMark&amp; stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, IntPtr ptrLoadContextBinder)
  at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, RuntimeAssembly reqAssembly, StackCrawlMark&amp; stackMark, Boolean throwOnFileNotFound, IntPtr ptrLoadContextBinder)
  at System.Reflection.Assembly.Load(AssemblyName assemblyRef)
  at Xunit.Runner.VisualStudio.VsTestRunner.GetAvailableRunnerReporters(IEnumerable`1 sources) in C:\Dev\xunit\xunit\src\xunit.runner.visualstudio\VsTestRunner.cs:line 711
  </code></pre>
  
  <p>Error happens only in one complicated project, with simple projects debugger starts and works properly.</p>
  
  <p>Debugging in Visual Studio works ok. 
  I would appreciate a hint of the direction to look for possible solution.</p>