I've uninstalled plesk from server, rebooted, and reinstalled.
Now services start, but plesk doesn't care about data.
In windows' folders there are my clients' files but plesk doesn't recognize them.
Tried also to re-create a couple of domains but plesk replies with errors.
Now I'm copying all useful data in another server and I'm gonna start over with plesk installation.
After that how would be possible to restore my presets and configurations from the copy ?