If you have some recent backup file from that controller try following:
- manaly reinstall the SW in the controller, after you first log in set the new password for system user
- FTP to the controller and download usrprfle.db file (
ftp://system:@<controller ip>/db/database/files/usrprfle.db)
- in the backup file replace \db\database\bak_files\usrprfle.db in the \vmail\temp\db\backup\systemdb.tar with that one you have just downloaded
- do a restore with this updated backup file
- log in