If the data was converted to version 2018, you will not be able to open in version 2017.

If you want to use version 2017, you will need to restore a backup that was made before converting to version 2018.

hi, all my data is on .ptb 2018 backup file due to update and i have sage 50 quantum accounting 2017 product so, could you assit to restore the backup or update procedure.. thanks