DWG File Format
Files saved under AutoCAD / BricsCAD can not open in other versions of AutoCAD / BricsCAD
Latest versions of AutoCAD and BricsCAD save their DWG files as a DWG 2021 format.
This DWG format applies to AutoCAD 2020 onwards and BricsCAD v20
If you are working with previous versions of AutoCAD or BricsCAD, we recommend to set the default save format to 2013.
In BricsCAD, go to Settings > Settings
And change the Save Format option to DWG 2013.
You now will be able to open DWG files created in earlier versions of AutoCAD / BricsCAD