I had been using an older version of Groupy, and while I love the ability to save/load groups after logging in to Windows. The problem was that any time I clicked to open a file, explorer would freeze for 5-15 seconds (title bar goes white, etc). For instance, trying to open a VS project, then having to wait for it to unfreeze to open the associated Unreal Engine project was getting annoying. 

So, I uninstalled Groupy and all settings and the problem went away. I figured maybe it was a setting glitch so I reinstalled and the problem returned. For the heck of it, I uninstalled it again, then purchased and installed Groupy 2. Same problem, maybe slightly less freeze time before I could click again. So I uninstalled v2 and the problem went away. 

Not sure what the problem is but I miss using it