Awesome idea Sandra – it worked for me – a MILLION thanks. The share menu was available for other projects/timelines but not for the big honking doc I spent a year working on and needed to output today.
Not sure I can express in words the extent of the pit in my stomach facing this grayed out menu for the first time (have been test exporting all along, backing up, no issues). Waited for the background/task rendering but that didn’t provide relief and I’m not a big believer in the pref trash/reinstall software options when things like this come up so I mined the forums for suggestions and yours made sense to me/my situation.
Some of the last-minute B-roll I added from older events were the offenders. I clicked through and found about 8 clips that wouldn’t reveal in the finder, re-imported them, and voila – the menu appeared!! Seriously, thank you so much for posting your question and resolution here – it really saved my project today!