The .NET Framework 4.6 RC Multi-Targeting Pack is a package that enables developers to build applications targeting the .NET Framework 4.6 using either Visual Studio 2013, Visual Studio 2012 or third party IDEs. You need to download and install the .NET Framework 4.6 RC prior to installing the multi-targeting pack.
catch (MyException)in your code that works, enabling the rewriter will force you to
catch (AggregateException)instead. Also it breaks cancellation, turning all canceled tasks into faulted ones.