Re: Error during the Central Instance stage (database instance connection)

HI Samid,

pls check this one way its is possible

it's also possible that you're trying to use SQL Server Authentication without having enabled it. To fix this, right-click Properties on your server instance in SQL Server Management Studio, and update the security settings to include "SQL Server and Windows Authentication mode".

OR

1. login Mirosoft SQL Server 2012 with windows authentification.
2. right-click onto the server name in Object Explorer and click Properties
3. In the new tab click Security
4. select SQL Server and Windows Authentification
5. Ok
6. Close the SQL server management studio.
7. start+run
8. write services.msc
9. search for SQL there and restart all services.

Regards

Nayeem