Maybe all components are virtual and therefore no components are referenced?
Version? License? Read-only?
There are 5 top level, non-virtual sub assemblies in this file. I am using SW2015 SP5
Does a Pack and Go work instead of Save As? It should include the components.
I still have no idea what is causing your UI issue.
Mine has done this on one drawing file, also.
Can't figure out why.
My guess would be it opened up as a "Read Only" file - or someone else opened the file from another computer now when you try to save then the references would be grayed out because of the read only status...
I am using SW2017, and have a file that this has happened to. Both the drawing, and the assembly have the issue. Can't figure out why.
Tried the "save as copy" options?
I've only seen this issue of a greyed-out "Included all Referenced Components" checkbox when none of the referenced files can be saved. Either because they are all read-only, all future-version files, or some combination.
For reference, Solidworks uses this feature manager icon for future version files: From 2019 SOLIDWORKS Help - Future Version Components in Earlier Releases
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