I am trying to import DWG files over to ArcMap, but none of the data show up on display. To preface this, I did not create these DWG, and these files were not given a projection and coordinate system. And I work on AutoCAD Map 3D 2011. So I have a couple of questions about this:
Well, I think you'd better find answers in an Esri forum, not here, sir.
Anyway, try to _MAPEXPORT from Autocad in .SHP format, then import the resulting shapefiles in Arcgis.
To add a DWG to ArcMap you use the button with the + sign. A extension is not necessary.
What coordinate system has the dwg data? In what coordinate system is the ArcMap data frame?
If the coordinate systems are equal, it is not necessary to assign a coordinate system to the dwg.
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