Noted at https://support.microsoft.com/en-us/help/4027979/windows-fix-problems-with-homegroup-after-updating-or-upgrading-to-win
You should move to the other sharing method when you can.
Windows 8.1 ipv6 is checked/enabled yet it keeps telling me it isn't I even used admin cmd prompts seen in another video to reset it & ipv4 & netsh winsock catalog reset on both it & a win10 computer, neither will create a homegroup, in both I also turned all services related to automatic,such as peer to peer & homegroup, 4 services to automatic as other videos told, the Win10 POS! keep telling me I cannot create a homegroup after all that & the win 8.1 keeps telling me ipv6 is not enabled & it is, even tried to reinstall the protocol, I HATE WINDOWS!!! 10 IS THE WORST POS! this is So damn aggravating, all fixes found online so far, don't work. ***? anyone figure this out? Setting up a homegroup used to be easy, not anymore, of course. All solutions I've found online & tried don't fix this problem, both networks are set to private too,btw & doing that in Win10 was another pain in the ***, after 2 attempted fixes failing, I had to use a registry edit just to my home network set to private, Win10POS!