I have tried uninstalling and then reinstalling framework.net, paint.net.
I have upgraded the Windows installer from MSoft to 3.1.
I have used registry cleaning software, Windows fault-finding software.
I still cannot get P.net 3.1 to install on my system.
I have scanned through the solutions provided by others, but they don't work for my system!
I would like to get another copy of v3.0, but where?
Failing that I will have to revert to my previous, pre paint.net, application.
Pity. But thats life I suppose!