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Library module Syncing Issues on LR Classic

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Premium Classic Member
Premium Cloud Member
Aug 6, 2015
Lenexa, KS
Lightroom Experience
Lightroom Version
Operating System: MacOS Sierra
Exact Lightroom Version (Help menu > System Info): LR Classic 7.0.1

I use two computers, a desktop and a laptop. I use an external drive that I swap back and forth to keep things in sync. I am having problems with syncing - I want to sync a few collection sets so that I can access them on my iPad and online. I did that prior to upgrading to LR Classic with no problem and had about 200-300 photos to sync. I've found LR Classic to be virtually unusable because it keeps trying to sync thousands of photos, I'm not even sure which ones or how many total it's trying to sync. I have over 20,000 in my catalog but it will start syncing and slow down to a crawl or stop completely after a few thousand photos. I can pause the syncing when I first start up LR and things work fine - but now I've lost the ability to sync anything.

I'm at a loss as to how to fix this. I've uninstalled LR Classic for a while to go back to LR 2015 where it was working fine - but now even that has the same syncing issues. The next option I'm thinking about is to go back to an old time machine version and just stick with LR 2015 until Adobe gets the bugs worked out - but I'm a little nervous about what specifically I should overwrite, and I sure don't want to restore my whole systems on both computers. Any suggestions from anyone on any of this?
Generally speaking, Lightroom (CC2015 or Classic) cannot arbitrarily start syncing "thousands of images", without some form of user intervention (inadvertently perhaps). So what you describe should have a root cause that we need to figure out in order to get things back on track. Can you start Classic using the catalog that's giving you the problem, and before it starts bogging down through excessive sync activity you should pause syncing (click on the ID plate to open the Activity Centre, then click on the "pause" icon alongside the "Sync with Lightroom mobile" entry). That'll give us breathing space to start figuring out what's happening, and the best place to start would be for you to post a screenshot of the Preferences>Lightroom CC tab. There'll be information in there that should help.

You could also look at the total number of images in the All Synced Photographs special collection in the Catalog Panel in the Library module, does that number reflect the 200-300 that you thought you had synced, or is it much higher?

If it's higher, look down in the Collections Panel to see if you can identify any collections which are set to sync (will have the double-headed arrow icon in front of the collection name) and which have a much higher photo count than expected. Are there any collections there that are set to sync unexpectedly?

Have you been looking at the new cloud app LR CC by any chance? Have you added any photos to it?
Jim, thanks so much for responding. You've zeroed in in a couple of things that could potentially be the issue. I did install both LR CC and LR Classic at the first opportunity. I was anxious to get rid of the drive swapping and thought the cloud was the answer. Lesson learned: look before you leap. I actually upgraded my storage and uploaded the 20,000+ photos. And of course LR Classic did nothing but grind and was unusable so I backtracked, uninstalled both on both computers, and deleted ALL the photos from the cloud so I could start from scratch. Reinstalled LR 2015 on my desktop, got it up and running yesterday using my old LR catalog, and selected the collections I wanted to use with LR Mobile. All Synced Photographs reflected the 200+ photos I want to sync. I actually got some work done. So I moved to my laptop; I'm leaving on a trip tomorrow and would like to get some work done on that as well. I did the same thing I did on my desktop but that's where the syncing issues started. There are currently 211 photos in the All Synced Photographs special collection, 199 photos in Adobe Lightroom for Web. I just opened up LR Classic on my laptop to check the actual numbers on that collection, paused the syncing, came back here to type and it's already locked up again even though the syncing was supposed to have stopped.
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Classic shouldn't lock up on syncing 200 photos, so I suspect there's something else causing that. What are the system specs of the laptop?
The laptop is a MacBook Pro, MacOS Sierra Version 10.12.6 (same as my desktop), 8 GB memory, 2.6 GHz Intel Core i7 processor. Even though LR 2015 is working on my desktop - 16 GB memory, 3.2 GHz intel core i5 - I haven't tried to reinstall LR Classic there since I don't want to mess with what is working - it says it is syncing 5,216 photos. I pause it immediately to keep it from locking up based on experience. But there are only 209 photos in the "All Synced Photos" collection.
That 5216 number probably stems from the 20k you put into LRCC. Although you have since deleted them from the cloud, the laptop version (or do you mean the desktop version?) is still "catching up", so perhaps now that you know where the excessive numbers are coming from, it might be OK to restart sync and just leave it alone for a while to get itself straightened out. What might be more of an issue is how many of the 20k images that you put into LRCC might have already synced back into Classic/CC2015 on the laptop/desktop. Deleting those from the cloud does NOT delete them from Classic/CC2015, so you might have a lot of Virtual Copies that you don't want in the catalog, but you won't know that until the syncing finally stops and you can assess the situation.

Personally, I'd try to just let things be to see if the syncing sorts itself out.....if not there are probably some more drastic measures that can be taken.
Both are the desktop versions, right? I'll give this a shot on my iMac and keep my fingers crossed that it doesn't lock up like it was doing on the MacBook Pro. I'll post the results either way.
Hmmmm... I tried to sync on my iMac, which is running on LR 2015. It hasn't locked up but has said it is syncing 5,155 photos for the last hour and a half. There are two photos in the "All Sync Errors" collection and five in the "Synced Duplicates" folder if that makes any difference.
Have a look at the Lightroom CC tab in your Lightroom Preferences, there may be some clues there as to what's holding things up.
You are good! Somehow the place to store my Lightroom Photos on the Lightroom Mobile tab is pointing to a random photo folder. And within that photo are many, many images that shouldn't be synced and shouldn't be in that folder. It must have been some kind of massive drag and drop error on my part.

Where should that be pointing? Since I'm back to using an external drive and swapping it between my two computers would it be better to put the Mobile Storage folder in the external drive so that both computers are using the same folder, or put a separate folder on each computer? My instincts say the external drive but my instincts have led me down some bad paths lately.
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Lightroom Mobile preferences should be set to the parent folder where you store your imported images. Earlier versions of LRCC2015.x set a unique system generated file name like "e3eabcca0a7849b7b85c99004e5a4fb8" Now if you import by date, Lightroom mobile sync'd files will sync to these same date named folders or you can chose ONE folder to receive all images sync'd from the cloud with LR mobile.
Screen Shot 2017-11-01 at 4.11.05 PM.png

Right now LR is trying to sync every image in the cloud down to your LRCC2015.x catalog. Make sure that all of the photos at Adobe Photoshop Lightroom are ones that you want to sync back to the master catalog.
Thanks Cletus. I've set up the folder, synced everything up, and I'm hopeful it will be smooth sailing here on out. Enormous thanks to both you and Jim; this has been weighing on me.
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