Have you tried running AUDIT on the dwg?
I have. I don't have the output, but the first audit was done without repairing, and it found 2 errors.
Second run with repair, found and only repaired 1 error. It wasn't not a visible object.
Still remains is the invisible 3d object with Bad Entity Name.
If the problem wasn't so rampant across so many drawings, I would just perform a copy paste into a new drawing, and be done with it. Ultimately my goal is to find and purge many drawings of these types of bad enames, but I was hoping someone here has seen this before so that I can try to find some characteristic to help with the purge.
There are more examples, but I figured simple questions get quicker answers.
Ex. I have identical CADWorx objects reported in the .dwg model space dictionary with the exact same xyz, but only one is visible. The other reports identical dxf data, but cannot be selected, and handent returns Bad Entity Name.
Of the 500+ project drawings investigated, I have 48 drawings with 337 duplicate (invisible) objects (no coincidence it is CADWorx). So, erase the invisible one in lisp or .net is not sustainable because I haven't found a means to discover which one is visible and which is not. Only then can I write something to iterate and purge the drawings.