Registering a Database Instance within Control Center

Hello Everyone,

First time posting, appreciate your help.

The SAP Control Center is already installed, all of the agents are also installed as well as the SQL Server (SQL 2014) on Windows server 2012 R2.

However when I register the Database instance keep getting error 800, print screen below,

The SLD agents is configured properly as well as firewall deactivated, SAPServiceB1C has sysadmin permission on the database instance.

As you have noticed the test connection works fine however error 800 occurs when registering.

Please advise

Thank you in advance

Giovanni