[Samba] In Samba logs, I get " check_account: Failed to convert" or "check_account: Failed to find local account" error messages.

[Mark London]

Hi - On an older Ubuntu 18 computer, I tried to configure Samba, whose 
latest version available for Ubuntu 18 is Samba 4.7.6.   I successfully 
joined to our windows domain, according to all commands that I've run, 
including wbinfo.   I am running SSSD for domain login access, which 
works fine.  But when I try to connect from a Windows 10 computer to the 
Samba server, it says user and password is correct, and prompts for 
username and password again.   It still says that it is incorrect.   The 
samba log for that node, initially showed me this error:

[2022/04/18 01:28:38.164874,  0] 
../source3/auth/auth_util.c:1259(check_account)
   check_account: Failed to convert SID 
S-1-5-21-1078081533-1580818891-1957994488-2127 to\
  a UID (dom_user[PSFC\mrl])

I couldn't find any any solution on the web that useful.     Then 
something I did, caused the error message to change to this:

[2022/04/18 02:05:39.810294,  0] 
../source3/auth/auth_util.c:1267(check_account)
   check_account: Failed to find local account with UID 3000 for SID 
S-1-5-21-1078081533-\
1580818891-1957994488-2127 (dom_user[PSFC\mrl])

I don't have a solution to this error either.  I don't know what to try 
next.   Any recommendations (besides upgrading to Ubuntu 20)? Thanks. - 
Mark