Thank you very much. Renaming the database file did it for me too. It was the missing link.
Do note, if it has a lot of banks and patches, when you first open DX7 V, it will be empty, no patches, nothing. But it is working in the background. Wait a bit, check for the database file being written to disk and refresh a few times until it stops growing. Then close DX7 V and reopen it and your banks and patches should now be there.