Symptoms
After an installation of visual studio 2015 the following error was getting thrown when trying to open k2 projects:
Unsupported
This version of Visual Studio is unable to open the following projects. The project types may not be installed or this version of Visual Studio may not support them.
Diagnoses
As it turned on the given client machine the client tools for blackpearl had not been installed.
Resolution
Installation of the client tools allowed the user to open the needed visual studio projects.