Error occurred during <DWG, or DXF> export. 

Please open any drawing (*idw file);
Click File->Export->Export to DWG... --> Choose Save as type: AutoCAD DWG (*.dwg);
 Configure DXF File Export Options;
 Click Next;
 Configure (if need) Export Destination dialog settings;
 Click finish. You need to do this only once. Now you can use dxf output option in Wooodwork for Inventor.