Recover the .edfw files

I'm using the Efficient Diary for some time already. Recently I couldn't open the entries. It said F:\MyDiary.edfw isn't a valid Efficient Diary file. This software is discontinued. I can find the . exe files inside my F drive, and auto backup in C drive. Does anyone know how to fix it?

Already done the following before I request for a helping hand.
1. Check Backups, but not working.
2. Reinstall the software, not working.
3. Try some of the recovery tools, they can find the files, and recovered the files, but still can't open my entries.