Is there a way I can prevent this or stop it from happening, I'll have assembly, usually containing multiple assemblies and I'll open it up and go to close it and get this message:

I'll select save all, close the file open it, not do anything and go to close again and the same pop up comes up. Is there something I can change in my modelling to prevent this from happening? I gets annoying having this pop up every time a file is opened and closed.

I can't upload a file for proprietary reasons.