You are right. The IBExpert connection was set to local. Is it better to use always a remote connection (with loopback)?

We already changed the settings in IBExpert to the loopback connection, because we had some other issues while trying to connect to the database from two PCs at the same time. We haven't checked the nbackup yet, if it is better now. I will try it in the next days.

regards
Nils