download for paid version

1. This is because you have used a later version of the Free Edition to access your data file, that's why the data file structure is different and cannot be accessed by older version.

2. In this case, you may rename your existing data file to some other name and run your old version to create a new data file to continue.

3. Data file location:
C:\Users\<User Profile Name>\AppData\Roaming\Chrysanth\Data\DB.CSDB (Please note that this is a hidden folder in your system, you will need to make it visible by changing the Windows Explorer option first)