LONG story short: When upping from Win 7 to 10, I had to set up a new user. While the new installation imported the old user (say, "thomas"), I ha dto set up a new user (say, "thomas999").

The hOmeGroup finder found and connected to the old "thomas" homegroup, but it did not see any Group labeled thomas999. And when I tried to set that group up on ,y PC under thomas999, a message popped up and said I was not able to create a HomeGroup on my PC.

I Googled like crazy but can't find a reason why this is the case. And the new installation is under thomas999, even though the old username thomas is still there.

Please help me someone - thanks!