If you are trying to open a DWG file with AutoCAD and you get the message “Drawing File was created by an incompatible version” it’s because somewhere along the line your AutoCAD DWG files were saved with a newer version of AutoCAD.
All is not lost, you can make them open again in your version of AutoCAD, you just need to download the free DWGTrueView App from Autodesk – http://www.autodesk.com/products/dwg/viewers
Once installed, start DWGTrueview and open the DWG file in question, then save as making sure to select the lowest DWG file version that matches your version of AutoCAD.
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