Recently I ran into an issue where I had 2014 and 2015 installed because of an add-in issue I had with 2015 and it wouldn't let me open files in 2015 by clicking them. I've since deleted both versions and now only have 2015 installed because I've upgraded my BobCAD add-in that was giving me issues with 2015 to begin with. The program and add-in now work great together. However, when I try double clicking to open files I keep getting the prompt like it doesn't recognize solidworks is the program to open the files. It also has the "default for opening this program" box grayed out and can't click it. What gives?