What I mean is if I have NX 7.5, 8.0 and 8.5, and I need some parts to be compatible with NX 7.5 and others with 8.0, if I save it on a newer version, that becomes a problem.
This question has been asked and answered many times on this forum. Once you save a file you cannot go back to a lower version of NX it is upward compatible only.
Now there's nothing preventing you from opening say an Assembly in NX 8.5 which contains Components which were last saved in older versions of NX. Just that you need to avoid saving those Component parts if your desire is to keep them compatible with those older versions of NX. If these are common parts that will be used by several different assemblies, and you're no using Teamcenter, you can simply set those part files to be read-only and then you're safe to open and close them however you wish.
John R. Baker, P.E.
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