moving local sophos DB to new extrnal DB Server

Question

Hi all.. 
 we have sophos console 5.2, the plan is to upgrade to 5.4.1 then migrate to new server, then have the new server point to extrnal DB. 
 someone did the upgrade, and when i tried to migrate i faced an error during restoring backup DB as shown, you can see the existance of SOPHOSENC52.bac, i think it shouldn't appear as it is related to old version!, not 5.4.1!. what could be the problem here? shall i reupgrade the old server again? 
 
 and lets supose that the migration of sophos console 5.4.1 from win server 2008 to win server 2016 running SQL server 2016 was done successfully, then after migration we want to config that new server to point to an extrnal DB insted of local DB (moving local DB to external SQL server). they will give me that external DB instance and login account only. 
 what i understood is that i will modify registry values to point to that external DB: 
 HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Sophos\EE\ManagementTools\Database Installer 
 HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Sophos\EE\ManagementTools\DatabaseUser 
 and then delete the local DB 
 please correct me because i really got confused at this step!.

QC · Accepted Answer

Hello Roy Carlo Bago , 
 should have seen this yesterday: CREATE DATABASE permission denied in database 'master' . The logged on user doesn't have the necessary permissions on the SQL server. Usually if you run the installer it creates the Windows Security Group Sophos DB Admins , adds administrators and the "database account" to the group and creates the required login in SQL. 
 As for databases, database names and migration: 
 
 when the Management Service starts it checks for the existence of its associated databases 
 if it can't find them it terminates, otherwise it checks for a certain value ( UpgradeStatus on table Upgrade ) 
 if the status is 2 then the databases are "in production", otherwise it searches for the "newest" previous (supported) database 
 if it can't find one it assumes a fresh install, sets the status and starts using the database, otherwise it call UpgradeDB.exe with the applicable switches 
 UpgradeDB.exe copies the data from the previous database, if necessary applying the appropriate transforms; the old database is not modified in any way (neither taken offline nor dropped - if you want to get rid of it you have to do it manually) 
 
 I hope it is clearer now. 
 Christian