Thank you guys! The problem was that in Windows 10 I was unable to locate the Windows services to start the SQL Server. This is what I've got from dev,s:
"The service isn't running. In the windows search bar type 'services' and open the services applet. start SQL Server (SIXBITDBSERVER)"
In the beginning the applet didn't respond (I don't know why!), but after a couple of trials and restarts I managed to open it and to start the server.
Once again thanks for your help.
- Ruben likes this