Ok guys ……. I got the dreaded “Unexpected File Format” error on a project today. This was a model started from another model, sister residences. So now I’m worried the same will happen in my other file. I’ve renamed and tried the SBK file and got the same result. It started with not being able to save the drawing. so instead of working ahead I quit and have not been able to reopen. When I had it open and was trying to save it and I was getting an error Can’t Save. Then I tries to copy paste my model out of the file into a new SKP file and I couldn’t paste it. Right before all this happened I was importing some 2D ACAD graphics while working in the equipment group. After that is when it all went to hell in a hand basket. Can anyone take a look at it? any ideas or fixes.