I don't gety any errors with the dxf or dwg files, but most of them don't show up in the viewport when I try to load them.  There's no indication anything went wrong other than the scene is blank.  I checked for hidden splines or objects, and checked all my layers.  Still, nothing.  

The AI files do bring up errors.  The 2008 AI gives me a very specific error:

"Line in file exceeds 255 characters", and then it gives me the Improper file format error afterwards.  The other .ai in your file set simply gave me an improper file format error.

However, I was able to import one of the files, the** ServierplatteTest.dxf** imported just fine, when I adjusted some import settings.  See attachment.

In my opnion, I think the problem is going to be in the way these vectors were created, or exported.  I noticed the imported dxf contained a lot of messy vertex points.  It's very common, and somewhat expected, that normalization of the resulting splines will be needed on any imported vector file, but in this case, it seemed excessively messy.

Anyway, that's the result I got.  Hopefully it provides some sort of insight.  I'm ruling out a 3dsmax bug as the problem here, and leaning toward the vector itself, or export settings, as the root of the issue here.

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