I already did that (restored the Mac databases) but I still have the devices showing different databases available 
Did you do anything more than just restore? Did you clean any of the sync locations? Did you make backups of the databases (Database archive?)? exactly what steps did you take?
I might have renamed a couple of databases on the iOS devices. Not sure if I cleaned up anything or not. You are asking for exact steps … but exact steps would deviate from the definition of right mess I claim I got myself into 
Everything is so vague so little I can do. Good luck.
1 Like
Well, I was thinking more along the lines “throw everything away and restore the databases on one Mac. Then start syncing again”. Which is, of course, only a valid approach if you do have a reasonably recent backup.
Yes, sorry: I kind of gave up on DEVONthink a couple of years back so there is no log of exact actions. Now I was trying to see if I can give it a second chance 
I’m late to this thread and it’s early and I’ve not had a cup of tea yet. That said, you’ve not explained the problem well, but I can see you’re after a process to follow and if I’ve understood correctly:
You have multiple devices with different versions of databases, running different versions of DT and running two different sync methods. You’ve renamed some databases on your iOS. Assuming I’ve understood that correctly, others have touched on the solution here but here are the steps I would follow:
- Back up your Mac. Run Verify & Repair and check File Integrity before you start on ALL your databases. Your Mac should be your source of truth going forward.
- Turn off all your syncs on all devices. You should only have one running, and as you’re saying your Mac isn’t matching your iOS devices, they’re not working properly anyway. Your databases are now isolated to each of your devices.
- Set up one sync method following the manual, between one device and your Mac, for the databases that are on your device and are missing from your Mac. You should use Bonjour as it will be quickest and I’m guessing the databases might be big.
- Sync the missing databases to your Mac. Back up your Mac again (part of your problem is that you have no back-ups of these “trapped” databases currently).
- Repeat steps 3 & 4 for the other device.
- Your Mac should now have copies of all your databases. Disable sync on all iOS devices again and clear the sync stores (see manual). Now only your Mac is holding the databases.
- Tidy up the databases on your Mac so that they’re correct.
- Back up again once the databases are tidied up.
- Update your iOS devices so you’re running the supported version of DTTG. Your iOS devices will be empty at present as the databases are only on your Mac.
- Update your Mac if you’re running the old version of DT on there too (I couldn’t tell if you are).
- Set up a sync for both your iOS devices, syncing the databases that you need to each device. Bonjour would probably be best, and this will take time again if the databases are big.
- Never mess with sync methods again
I think that will sort all your problems, but there’s a lot of human labour involved because your renamed databases on your iOS devices will need checking and correcting by you once they are on your Mac, which depending on the size of your databases could be hours of work.
@BLUEFROG please can you check this methodology in case I’ve missed something?
2 Likes
Very good for a tea-less step-by-step 
I would add…
Step 6.5… on the mobile devices, left-swipe the databases and delete them. On any other syncing Mac, not the primary one where the database will be curated, select each database and use File > Delete Database to remove each of them.
And on step 11, you would import the databases to DEVONthink on another Mac or DEVONthink To Go.