License Manager exception (2.6)

I am having a problem with “Remove All Licenses” on my Windows 10 PC for nwoods 2.6.

I get an ArgumentOutOfRangeException: Parameters Year, Month and Day doesnt describe a valid DateTime.

What should I do?

You may need to manually remove the keys in the registry (press windows key, type regedit), they should be at

HKEY_LOCAL_MACHINE\SOFTWARE\Northwoods Software\Go.NET

or perhaps the same location in HKEY_CURRENT_USER