title: Is Platform Toolset v110 incompatible with .NET 3.5?
body: <p>This is with Visual Studio 2012 Ultimate Update 3.</p>
  
  <p>I have a C# project that targets .NET 3.5. This project uses a C++/CLI dll which is also compiled for .NET 3.5.</p>
  
  <p>I have noticed that if the C++ dll is compiled with Platform Toolset v110, then although I can add it to the C# project, and see the types in Intellisense, the compiler itself doesn't see any of the types. It complains that they do not exist and that I am missing an assembly reference. This does not happen if it is compiled with Platform Toolset v90.</p>
  
  <p>If I then re-target the C# project to .NET 4 or 4.5, then it sees the types alright. The types do exist in the assembly and can be seen in the object explorer or Ildasm.</p>
  
  <p>It therefore seems that the use of Platform Toolset v110 makes it impossible to use the dll from a .NET 3.5 project, even though the dll is compiled for .NET 3.5.</p>
  
  <p>Is this normal and/or documented behavior? Is there any way around this other than either downgrading the C++/CLI project to Platform Toolset v90 or upgrading the C# project to .NET 4?</p>