Has anyone ever seen this message before or know what it means?
This error usually come hen you're trying to open a higher version file in lower version.
The drawing was created with SW2015 SP5 Win10. It was created on a desktop that also has SW2016 SP2 installed. I was able to open the file and save with SW2015 on my Win10 laptop that does not have SW2016. I can now open the drawing in SW2015 on the desktop. So, this sounds like some kind of conflict between SW 2015 & 2016 installed on the same computer.
This is one of the more useless messages that SolidWorks displays. Our users get it opening parts, assemblies and drawings and so far we cannot find any root cause. Sometimes just trying to open the document again solves the problem. Other times, you need to close and re-open SolidWorks before the message will go away. Sometimes we need to clean out the auto-back up folder. Sometimes, as you found out, someone else opens the document and saves it and then you can open it again. So that is why I say it is a useless message (our VAR has not been able to give me a clear reason for the message either).
Do you get this message on computers that have both SW2015 & SW2016 installed? What Windows Version?
Seen this a few times in the last few months, and you need to use SW rx and
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