P: Lightroom Classic: no longer syncs completely, successfully.

No, Lightroom Web does not show any sync errors in my case.

My OS is Windows 10 64bit Built 19041.630.

I am running Lightroom 10.

My phone is a Samsung S10+ running Lightroom Mobile v6.0

Lightroom CC is on a Surface Pro (also Win10) but not used in month (version 9.4), since sync take hours if not days to finish.

As said, synching problem in my case only effects the direction Lr Classic  => Mobile. Only RAW-Images in non-DNG-Format with no lens data are affected. If I remove those from the queue syncing works in both directions (which is obviously not a solution, only a short-term workaround).

Give me an overview of your sync clients:

I know you have Web and Lightroom Classic. Do you. have any devices, other computers, etc. Please list all, devices attached to your Adobe ID and their current OS and LR version.

Example: iPhone 10 - iOS 14.2 - Lr 6.02.

@hans_rupert Me too, I was an Apple-certified Mac Sysadmin, also for 25 years, mostly in New York City! Small world, huh? I still go by the dictum "computing is like an iceberg, 85% is the OS, 15% is the app"! As to your sync issues, I will add that my experience with Adobe's backend authentication servers, over 25 years, has been a freakin' nightmare! I can't TELL you how many Creative Cloud users I've had to delete and recreate in corporate environments, because nothing else would get them back working again. So maybe it's not your Mac?

*carlos_cardona Also, I'm not sure if you read my original post, but I did indeed create a fresh, virgin account on macOS, AND a new Adobe account to sync to, just so I could test such a theory, but even that got stuck.

*carlos_cardona Well, I've been doing UNIX and MacOS sysadmin for 25 years, and I'll just say that if this is the kind of voodoo housekeeping necessary to get Adobe Lightroom to run properly, then Lightroom needs to be rewritten from scratch. This is the kind of disastrous system corruption that led me to abandon Windows 25 years ago for NEXTSTEP (now called macOS, funny enough)

I'll try this all as a last resort, so thank you for your efforts with my problem.

@Rikk Thank you for the reply, however:

#1 – I've never seen this "Sync Errors/Issues Album" you're talking about on Lightroom Web. All I see is the activity alarm bell icon, the cloud storage icon, and my account avatar icon.

#2 – No changes could be made per your Step 1. I did, however rename a few collections on LR Web, but they're not showing up in LRC on macOS.

#3 – Nothing ever shows up here anymore. It used to of course, but not anymore. Now the main sync panel (cloud icon, upper right, small) just showed the very stuck "LOCAL ACTIVITY syncing 68 photos" forever and forever.

#4 – I assume this is the "nuclear option" you alluded to. I've done this with no success at least a half dozen times in the last 3 months. It never seems to help, sorry.

Agreed on all counts. It has actually been broken for me since about v9.3

ok, here is some more info about my problem after spending the evening narrowing it down.

After synching files one by one I realized, that there is a pattern to those files failing. In the end 16 images will not sync whatever I try. The following might help to further investigate the issue on Adobe`s side:

• All images that failed where shot with a manual lens where no exif data was transmitted from the lens. So all images have 0mm focal length and f0 as aperture
• All images were single exposure, ORF (OLYMPUS-Raw-Files). Images that were bracketet or panos merged in Lightroom as a Pano/HDR-DNG-File do sync!

So proprietary RAW-files (non-DNG) with no Lensdata do not sync in my case.

This is by no means a solution, but maybe it helps someone from Adobe to fix the issue.

My OS in Win10, but I already tried deleting the lightroom cache and also did drive maintenance recently. But that did not help either

You seem to have tried the usual fixes, so let's concentrate on the Mac OS, by giving your Mac the "once over" to delete more caches and application states.

Download the free Onyx (https://www.titanium-software.fr/en/onyx.html), select the Onyx version for your OS, download, run it, reboot.

In Onyx run almost everything in the Maintenance tab, deselecting things you may not want deleted, like Launch Services. Hit the "Options" button across from "Internet" and check/deselect more stuff like Cookies & Other Site Data, Browser History, Form Values, (which are OFF by default), but make any other choices you want to keep. Don’t know what something is? Google it, or ask me, or don’t run it, then hit Run Tasks. After it's done it will ask for a reboot. You will see you've gained some hard drive space, but try to use it again.

Also try to fix any directory damage by running Disk First Aid from Disk Utility: boot into Recovery Mode, (hold down Command-R when booting). When you're in Recovery Mode go to the Utilities menu and launch Disk Utility, select Macintosh HD (or whatever), and say Repair Disk. When done go to Apple Menu for Startup disk and restart normally.