When trying to save a file as an STL can't even get to the options menu. Part is not big.
Can you post part here
I've seen some like this few times before. There might be a feature on your part caused this issue
Pretty complicated part:
I saved it as SLT format without a problem !
..no problemo using 2017sp4.1 ...
Can you post part here
I've seen some like this few times before. There might be a feature on your part caused this issue