When updating DP 6/7 to DP 8/9, these file names are not converted from the old IDB files to the new DCBF files of version 2.
The DP code is able to read these old files, although the old database engine is not installed anymore.
So we have a fully functional IDB after the update and detail file browsing for restore is possible.
omnimigrate.pl -start_catalog_migration
omnimigrate.pl -stop_catalog_migration
omnimigrate.pl -report_catalog_migration_progress
omnimigrate.pl -report_old_catalog
omnimigrate.pl -cleanup
omnimigrate.pl -remove_old_catalog