[in menu Modify]
This function adds encoded copyright information to the MIDI file. In cases that somebody illegally removes or changes the standard visible copyright field, the secret copyright information remains in the file hidden. The secret copyright can prove your copyright when somebody else tries to steal it.
If a secret copyright (done with GNMIDI) already exists then it displays the secret copyright information.
If no standard and no secret copyright found then program asks for a copyright line. Use only ASCII characters (characters blank - ~), other characters (like international characters e.g. ü) are not stored. An optional password could be entered which can be used to delete the secret copyright text later. You must remember the password. The entered password is not stored in the MIDI file. You must remember the password.
Delete secret copyright
The show secret copyright dialog contains a delete button. You must enter the password that was used during entering adding the secret text.
If no password was used or password forgotten then you need to use your midi file backup.