So I'm trying to reinstall ARIS and connect it with my DB Server (on MS SQL Server). I don't delete the old database in my DB Server because a lot of my works an configuration is in there. But when I trying to connect it with my DB Server, it got an error "Schema ARIS_MASTER is not empty".
I think the approach could be to install ARIS with its builtin "standard database" (PostGreSQL) just to have ARIS Server again running. And then change/switch it to your existing external DBMS guided with some instructions from Global Support of Software AG.
