It is hard to tell what is happening from here but at a guess
- The current version of Manager could not read your old business files as they were too old
- The new version may have created a current version (blank) database file
- The older v20.9.89 Manager recognises the blank file was created by a newer version of Manager.
So your problem now is probably your application data directory has very old and very new files in it which for which no version of Manager is happy with both.
If I have guessed correctly you need to
- Go to your application data directory see
Application Data: Manage application data folder contents | Move desktop application data to another folder | Reduce data file size | Open a data file directly - The default location in Windows is c:\Users\ < Your Windows login > /appdata/local/Manager
- Make a copy of all of these files (a back up in case something goes wrong)
- Remove the files with todays date
- Restart Manager version 20.9.89
- If your data is then available
- Install the current version of Manager