New
#11
Try
net localgroup administrators hola /add
again with "administrators" typed exactly as the first item in the list above without the asterisk *
That should work. If that works and Windows still fails to log this new administrator into the system then we can try two more things before I suggest you do a repair installation:
1) check integrity of system files:
sfc /scannow
2) re-register OLE classes
for %a in (c:\Windows\System32\*.dll) do regsvr32.exe /s "%a"