title: How to fix "interface ICorProfilerInfo3 not found"
body: <p>I am trying to trace .NET application using Datadog .NET Tracer.
  <a href="https://github.com/DataDog/dd-trace-dotnet/releases" rel="nofollow noreferrer">https://github.com/DataDog/dd-trace-dotnet/releases</a>
  The application and the tracer are installed on Windows 2008R2SP1x64 Std with .NET Framework 4.6.1.
  It fails to trace with the following warning messages:</p>
  
  <ul>
  <li><p>.net tracer log:
  "Failed to attach profiler: interface ICorProfilerInfo3 not found."</p></li>
  <li><p>Windows Application Event log:
  "NET Runtime version 2.0.50727.8800 - Failed to CoCreate profiler."</p></li>
  </ul>
  
  <p>The requirement for the .net tracer is .NET CLR 4.5 and above.
  My understanding of .NET is that CLR is a component of the framework, hence CLR version is same as framework version.</p>
  
  <p>I'm trying to understand why .NET runtime version (2.0.50727.8800 according to Windows event log) is older than the framework (4.6.1 according to the Windows control panel).</p>