I am having the same problem, but it started to occur recently. I bought PD11 three weeks and it was working just fine. It started to mess up today. I haven't installed any updates today, except if Windows 10 decided to do it for me 
I am downgrading to 10 to see if it helps, but not sure if my PD11 license with work with it...
[EDIT]
My PD 11 license did not work with PD10 unfortunately, so I'm left with the hope this can be fixed soon.... I wasted whole day fighting this bug. I'll just move all my project into vm.
Please let me know if there i any diag tool I can run on my machine to help resolve this issue.
Last edited: Sep 27, 2015