Can't start local SLD server (NW 7.0)

Hello,

on my local NWA 7.0 I created http-destinations "SLD_DataSupplier" and "SLD_Client" (and gave rights to users) as in the documentation. On the SLD home page, the check returns 'Ok' for the server but "Not Ok" for the Application side, apparently because the SLD server is down. Trying to start it with the "Start server" button leaves it "stopped". What did I miss?

Thanks and regards,

Jens