6.0.6 hangs upon opening

I just downloaded 6.0.6 to replace 4.0.4 that I’ve been using for a few years, because 4.0.4 started to hang a few days ago. 6.0.6 still hangs (at the splash screen) when I try to open it. I’m using Mac OSX 10.9.5 on a MacBook Pro. What do I do next?

The first thing to do is to reset your user profile. See How to reset user profile on Mac OSX 10.8 (Mountain Lion)

Thanks! That worked. Back in business :-)}