After some try and Error i have now all the clients working and doing the backups correctly (Windows and Linux clients).
I produced a lot of junk (double backups) in this process, and i pruned all existing volumes, deleted them in Bacualaris int the volume-section. I also deleted the volume-files on the actual storage-server.
When I start an new Backup it start counting from the last existinge volume, in this case Vol-0013. Is it possible to reset the database to initial state so the volumes start getting numbers beginning with Vol-0001 again?
I've seen the other post about 'How to Clear/Delete Job History in Bacularis Web Interface?' - ther was a reply that mentioned:
For PostgreSQL
delete_postgresql_tables
make_postgresql_tables
Maybe this will work as well for my situation? But i don't have those scripts, where are the y included, meanig in which Ubuntu .deb paket?