If you are not able to connect to newly created SQL DB from newly installed GPOADmin 5.21 instance.(If you use custom port than also its not accessible)
When tested with NT authentication and account having full access to DB and also with local SQL acct and both fail with same error, cannot connect to SQL.
When tested connection to the DB via UDL test and If you use the SQL server FQDN if connects successfully but if you use SQL servername\instacename, UDL test will fail to connects.
In GPOADmin 5.21 and we did find an issue not in how we set the encryption for the database server, rather in where we check that the SQL server is a valid server. The method we are using that was introduced in GPOADmin 5.21 will check in AD that the machine entered into the SQL server dialog box is present in AD. If it is not the connection will fail marked as the server does not exist.
This is why when you uses the FQDN to connect that it fails. The FQDN is present as a CNAME record in DNS, however it does not have a corresponding computer object in AD and fails the existence check.
This is a known issue logged on defect ID 587444 and was resolved on 5.21 Update 1.
It is recommended to download and install 5.21 Update 1.
If you need to create the DB manually please use the scripts that comes with the GPOADMin 5.21 and connect to the database.
