I created a .dwg file in Carlson Civil Suite 2018... I brought in points surveyed for this project. I worked in the file placing line work for the project. This .dwg file worked fine last week. This week I went to open this same .dwg file and I get a message from IntelliCAD. Error: Invalid group code. Unable to open this drawing. It contains incorrect or corrupt information. The RECOVER command may be able to extract undamaged information from this drawing. Do you want IntelliCAD to attempt to recover this file?
I click "Yes". The next message that comes up says: IntelliCAD Error: Invalid group code. Unable to RECOVER this drawing. It contains incorrect or corrupt information that is too extensive for repair.
So is all my line work that I did for this .dwg file gone? Do I need to create a whole new .dwg file and start over? What can I do so I don't lose all this work in the future? More importantly, what did I do to cause this? Any help would be greatly appreciated. Thanks!