Moved hosting to One.com – database connection broken

Hi.
I´ve done something wrong while moving my site Fotokunstner.no from one hosting service and over to One.com.

I took a backup of my site, uploaded it to the new server.
Then I exported my SQL database and uploaded it into the default database created by One.com.
Then I opened wp-config.php and changed the name, user and password accordingly.

Still the database connection is broken as I can´t access my posts either frontend nor through the backend.

Hopefully some of you knows how to fix it and willing to help me out. If you need more information just shout out.