Local user not part of any usergroup; can't add it to any; account not listed

Question

Removed a local user from the administrators group and am getting error 1317 on net command, trying to add it to a user group.

User isn't listed in users gui (cp, settings), but is listed on net user command (with an empty usergroup entry).

User profile content in Explorer and Registry entries are intact.

Is there a way to recover the user account, restoring the profile settings (or copy them to a new account)?

Update:

This is what net command instructs you to do, in order to add a user to a (local)group:
net localgroup <groupname> <username> /ADD.
This repeatedly resulted in net issuing system error 1317 ("The specified account doesn't exist").

This is what solved the issue:
net localgroup <groupname> <computername>\<username> /ADD (NOTE: don't use quotes in groupname, otherwise account will be listed as part of group, but not functionally recognized as such).
"The command was concluded with success". Account is now available and working.

Credit goes to: https://www.thewindowsclub.com/user-accounts-missing-windows

Answer 1

To add a local user to a local group through net command, you need to include computername, as well as username, as below (this isn't stated, or even implied, in net command help):

net localgroup <groupname> <computername>\<username> /ADD

Merely including username will result in system error 1317 ("The specified account doesn't exist").

From: https://www.thewindowsclub.com/user-accounts-missing-windows (NOTE: don't use quotes in groupname, unlike in the link, otherwise account will be listed as part of group, but not functionally recognized as such).