Hi,

I may have narrowed down the problem somewhat.   I've done more testing of other & older AutoCAD files & they work fine.  All files open easy on a double click. Newly created saved files also work fine.

The recent AutoCAD files sent to me ( that I'm having the issues with ) have been from clients who have recently upgraded their windows AutoCAD and windows Revit to 2017.   The files are posted & downloaded from clients ftp site.   One small size roof plan file is zipped & attached .

It could be that AutoCAD LT Mac just does not recognize the new windows AutoCAD version 2017 saved files yet.

PS .. These same files do open on a friends windows AutoCAD so it may be an issue specific to 2017 AutoCAD LT Mac.

JM