I get these ERRORS sometimes. Files get lost too. Try to do things a little differently. Yea it sounds weird but all CAD Softwares experience problems like this. Just know that for the most part it isn't you causing the problem. Many suffer the same trouble, even SolidWorks, Mastercam, Gibbs, Surfcam, and Catia. It could be anything from a Buffer to a Geometry Issue.
Just do your best to work around it. Save a Wire Frame Master drawing so you don't lose everything.
This was done in BCC
Toby D.
"Imagination and Memory are but one thing, but for divers considerations have divers names"
Schwarzwald
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
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