As soon as I add a tsconfig.json file to my Visual Studio 2015 web solution I get the above error.

Also this stops the compiler from re-generating JavaScript files even when I set "compileOnSave": true.

When I double click the error it takes me into the Microsoft.Typescript.Targets file which contains a lot of issues such as Unknown Item Group "TypeScriptCompile". In the error list these appear as warnings but they are there whether I have a tsconfig.json file or not.

Is there any way of solving it or getting more information on what the problem is?