Treehouse 2015 Error: The interface is unknown. (Exception from HRESULT: 0x800706B5)

I have multiple versions of solidworks installed on my machine (2013 SP5 & 2015 SP0). When i launch Treehouse with SW2013 open in background i notice the following error. clicking OK will not dismiss the launch and keep trying again and again.

SolidworksGeneral