Parallels 11 and now 13 open but then become non responsive

Hi.
I was quite happily using Parallels v11 with Windows 7. Mac OS v10.11.6 (El Capitan). After contantly being pestered by Parallels upgrade notices I decided to upgrade to V13, after than it all went down hill, now Parallels starts - then starts Windows 7 then it I get a beach ball of death and that's where it stays until I eventuallly have to restart the Mac, this happened every time. I decided to scrap the whole setup and start again, deleted Parallels 13 the windows 7, installed from scratch, but this time installed Windows 10, still the same problem, becomes unresponsive after only about 10 seconds. I have created a new user on the Mac and installed said versions from scratch, but still the same problem.
I eventally went back and installed Parallels v11 and a new Windows 10 version... but no, it's still the same. Lost for what to do next really! If anyone could suggest what to try next please?

 

Looks like I found the solution myself.