Metrolol

when the wp-includes folder was restored, it wasn’t restored completely. It was missing some files that prevented the editor from functioning and prevented the auto-update. All fixed by simply re-uploading the wp-includes folder.

Problem solved.

Cool, thanks! Hopefully this will work for WPMU as well ya? Don’t exactly know the distinction, so just making sure.

From my superior:
It’s not the normal WordPress install, it’s a WordPress Multisite (WPMU) network. Is there manual upgrade instructions for that?

His reply was that he fears irreparable data loss. He is considering hiring some on to help fix this, with that in mind.

What would you say to that. Is this method indicative of data loss?

I believe we have tried everything that could happen with Plugins and themes. As the quoted text from above states, my superior states he has tried disabling all themes and plugins and it still does not work.

I will forward him your suggestions regardless, but if these were to return no solution, would you have another option you would explore?
Thanks soo much for the replies so far guys! Really helps a ton.

Considering all possible options. From my superiors:

Thanks for troubleshooting. I don’t know for certain, but I don’t believe the posting issues are influenced by the WordPress version. We were able to post using this version of WordPress before, so I think it’s something else. I tried disabling all plugins/themes, so that’s not it. I’m really not sure. ??

We should look for advice related to WordPress 3.9. The research above is from 5 years ago. The maintenance file prevents anyone from seeing the site (they just see a notification “This site is down for maintenance and will return shortly,” or something like that). Deleting the file manually lets users see it again.

Let’s look for stuff related to people being unable to enter text into WP 3.9, keeping in mind it doesn’t appear to be the theme or plugins.

Does this help clarify the issue for anyone?

I had read that thread previous to coming here, and gave it another look over now that you linked it. I appreciate the reply, but is there anything in that thread that indicates its the same issue we are having?
Maybe its my interpretation, but the OP over there claims that there is just a message, and not an all-out failure of the system as we have.
I suppose the message IS the failure though, and its very likely that the two go hand-in-hand.

Sorry to be stingy, just trying to get back to normalcy!