It is possible (likely) that Solidworks will refuse to export components if some are imported via the 3D interconnect...
What are your settings in the " Import " options?
Are all the components in your assembly in Solidworks format, or do you have imported components in them?
Maclane, I disabled and re-enabled the export options but it doesn't work either.
By going through Mycadtools I have the same problem, the export is impossible in STEP.
bvergnieres, I tried the export in Ap203 and Ap214 but I have the same error message displayed.
I don't have a macro or configuration.
My pieces are in the same repertoire.
I've tried with different files but I still have the same problem
As another CAD software installed I have AutoCAD.
This afternoon I'm going to try a SW repair, I'll keep you posted.
Thank you for your help
By the way, I was saying to save your assembly in parts in a single fichier...@+.
AR. 
I was thinking of the same thing; another software that would have installed a version of the STEP " codec " that SW does not know how to use.
Speaking of codecs, @Charles Eugene_FRIEDRICH your SW can open STEP files?
Hello
Have you tried any other settings, such as unchecking Export Properties?