Big Sur 11.3 Issues with Photos Sync

Hi Lipolainen,

in my experience the problem is was the Photos Library.

I would try the following:

• Open the photos app
• Select all photos and choose "Export Originals". If you now get the message "cannot find Originals" you will have to find all photos of which Apple Photos cannot find the Originals anymore, although they are display fine on your screen. Then you will have to delete all those photos.
• Close photos and open it again with "Option-CMD" pressed and rebuild the Photos Library.
• Close Photos again and Restart your computer
• Connect your iPhone and try syncing via the Finder-syncing window.

I hope this helps. (If you do not get the "cannot find originals"-message, this fix does not help, I guess).

This is what solved the same problem on my Mac Mini M1 and iPad Mini (G5):

• I copied my High Sierra Backup photos library again to my MacMini M1
• Option-Click opened it in Photos. Photos updates it. Closed it.
• Then I Option-Click opened my non-syncing M1 Photos-Library and exported all new photos, which were not on the High Sierra backup from January.
• Photos could not find some Originals (which had been imported from iMessage). I will have to get them from iMessage again, I guess...
• Then I imported the new photos into the photo library from the backup, which is now on my Macintosh HD and set as System Library.
• Dragged the M1 library to the waste bin. Empty waste bin.
• Sync with iPad now works as expected.

I suspect the not found originals were part of the problem. Maybe a problem with iMessage and Photos.

You might give this a try resetting your iPhone: How to restore default iPhone settings without erasing your data

You'll want to take screenshots of all of your settings windows so you can return them to what you have more easily.

You may have an issue similar to what I just experienced. Check out the Syncing between Mac and iPhone stuck at "Reading Photos library" thread to see what worked for me.

Same problem since 11.3 update (April 27). Mac (MacBook Pro) makes a back-up of my iPhone - and that's it. No synchronising of photos from Mac to iPhone (iPhone Xs Max). Sync alternatives are grayed out. Last night I let run the sync around 12 hours: all the time only "reading photo Mediathek" (that's what it says in German), sync ended never. Tried to switch of photo syncing - no help: when syncing the "reading of the photo Mediathek" starts stubbornly all over again. Tried also to downgrade to the Big Sur version before 11.3 from a Time Machine back-up but even this seems to be impossible. Until 11.3 the transfer of photos from Mac to iPhone worked fine. Until appr. last autumn there were always problems with the transfer of photos. It seems to be an old Apple tradition to first solve a problem and then let it come back with the next update.

I am having the same problem with my iPad Mini (Gen 5) and Mac Mini M1

After upgrading to Big Sur 11.3 Photo sync does not work. I have 85Gb of Photos to sync via the USB-Thunderbolt cable, left it on for 12 hours over night. The sync status bar is moving, and the arrows are circling, but no progress.

After restoring to default settings II finally did a total reset and fresh install of the iPad, but still the problem persists.

I did a repair on the photos library. Photos now suddenly shows the message "Album anordnen" (German system=organize Albums), when I press on an album. The progress bar is moving left and right since 30 Minutes now.

There seem to be some serious bugs in Photos for M1/Big Sur.

Tried also to fix the issue by deleting the iPod Cache (which some years ago was really a way out of similar problems). Unfortunately, it did not work this time: same story as before, only "reading the photo library" one hour after the other without any results. As a temporary solution I simply send new photos to the iPhone via Airdrop. Somehow, I have the feeling that Apple is - for business reasons - not really interested in a reliable solution of the problem which persists since many years in a way or another (hundreds of duplicates on the phone, syncing only after many attempts etc). When looking on Apple's official support sites for a solution of Photo related problems I see all the time hints that I should use iCloud "to access your photos, videos, documents, notes, contacts, and more". Fine, but this has a price (200 GB/2,99€/month) to be paid to - Apple. And having bought an iPhone with 500 GB memory I don't quite see the advantage of using iCloud FOR ME (and not for Apple). From this point of view the fact that photo syncing functioned well approximately since the introduction of Big Sur until the recent 11.3 update seems to be a regrettable mistake which Apple now managed to correct.

Hi, dr. meguro and SafetySteve, finally found the time to try the meguro-fix and - a miracle happened, it worked! Thanks a lot, ein großes Dankeschön!

After deleting the missing files, Photos properly transferred everything, no duplicates etc. I found appr. 100 missing originals (out of appr. 53000 photos, some years ago I had scanned almost all my old analogue slides and negatives). About half of the missing originals  turned out to be duplicates (one normal file, one "missing").

Interestingly, almost all missing files were from Sept - Oct 2015.

And one more peculiarity: when now syncing I get a message, that certain video files cannot be transferred to the iPhone since they cannot be played on the iPhone. Moreover, the message indicates even the name of the file(s): 75F6DD40-B418-431B-86F7-F43A6684AC38.mov. Cryptical, isn't it? However, I cannot find such a file in my library, even not in the iPod Cache. At least for the time being, it is of no importance for me - as long as Photos simply skips this or these files and transfers everything else. 

Photos offers also a repair function. I wonder a little bit why Photos does not - when repairing and in case of necessity - display a message of the kind  "your library contains xxx files with missing originals which you should  find or delet, otherwise synchronising may not function properly". This could be quite helpful. But - Ende gut, alles gut or all is well that ends well!

I am unable to sync my iPhone 8 with iOS 14.5 to my MacBook running OS 11.3. The laptop will not recognize the iPhone when it is connected with a USB cable. Tried different cables, re-booting both the phone and the computer. Will not work. Why?