To David, personally I rely on the recommendations of my colleagues who rolled back their backend Access databases to Access 2013 (32-bit) late last year and have had no issues since then. All other posted solutions I've tried either only work for a few
weeks or not at all.
I agree with you on IT Dept not allowing non sanctioned MS fixes. It took a lot of convincing to have them try the server fix, which ended up impacting performance almost immediately. You take a credibility hit after that, and they're not so welcoming on
your next suggestion.
I fault Microsoft with not taking this issue seriously, coming up with a fix that works across the board & treating Access like a defunct database waiting to be pitched (a al FoxPro, DBase, etc).