ORA-12631 using Database Links with Oracle DBMS 19c on Windows Server 2019
For many years we have adjusted the configuration of our Windows DBMS hosts by revoking the Access this computer from the Network User Right from the Everyone group.  With previous versions of Oracle DBMS this did not cause an issue, but with 19C we found that we needed to grant this user right on each database link target host to the AD service account used to run each database link source host.