Hello there,
You can try the below steps and see if you can add groups. Open CMD as admin. Type the following command, and then press ENTER:
net user USER_NAME PASSWORD /add
In the above command make sure to change USER_NAME and PASSWORD with the credentials you want to use for the new user account.
After that, Please type the following command to add the newly created account to the Administrators group and press Enter:
net localgroup administrators USER_ACCOUNT /add
Sign out then log in with the new administrator account and see if the group is added.
Hope this resolves your Query !!
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