Move the windows server into a dummy workgroup then back into the domain it was originally on to resolve:

The Local Security Authority cannot be contacted

However you may get:

The following error occurred attempting to join the domain "abc.123":

The request is not supported.

Checking the logs we see this:

%systemroot%\debug\netsetup.log

01/23/2018 19:57:02:446 NetpIsTargetImageADC: Determined this is a DC image as RegQueryValueExW loaded Services\NTDS\Parameters\DSA Database file: 0x0
01/23/2018 19:57:02:446 NetpOpenRegistry: The image at C:\Windows\system32\config\SYSTEM is a DC: 0x32.

In this case find out the path of the DSA Database file:

Location: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters\
Field: DSA Database file

then remove it.  Or move it out of the way:

PS C:\windows\ntds> mv ntds.dit ntds.dit-bad
PS C:\windows\ntds> dir

    Directory: C:\windows\ntds

Mode                LastWriteTime     Length Name
—-                ————-     —— —-
-a—         1/23/2018   2:21 PM       8192 edb.chk
-a—         1/23/2018   2:21 PM   10485760 edb.log
-a—         1/23/2018   2:21 PM   10485760 edbres00001.jrs
-a—         1/23/2018   2:21 PM   10485760 edbres00002.jrs
-a—         1/23/2018   2:21 PM   10485760 edbtmp.log
-a—         1/23/2018   2:21 PM   12599296 ntds.dit-bad
-a—         1/23/2018   2:21 PM    2113536 temp.edb

PS C:\windows\ntds>

Cheers,
TK