I am tired of this and will make it my mission to get rid of the problem. I have tried other CAD programs (Briscad and ARES Commander) which do not have this problem but are inferior for the time being to Autocad. I Xref in DWGs from Sketchup and have to do it for any change etc. I then have to open those drawings and run a lisp routine to kill the NLS warning. Each main drawing has around 12 Xrefed DWGs for elevations, floor plan, roof, sections etc.  I attached the warning and a rectangle I drew in Sketchup and then exported from Sketchup. What is the proper channel to get this 6 year+ old problem fixed? I have submitted a "feature" request...Bug reports...posted to this forum like 100 times..... 

By the way I have tried every DWG version for Sketchup and landed on release 14 for the least amount of NLS warnings. Some give 2-3 per dwg. 

It tells me to goto the "Windows Control Panel".....uhh I am on a MAC so where exactly do I go? Do I need to install windows and goto the control panel there to fix my Mac?

Simple solution is add the recover option you get when you open it to the attach and refresh of xrefs. That way it can automatically fix the problems and not tell me about it.

If someone has found a solution please help.

Thanks,

Russell