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Issue with sync error: Sync encountered an error while syncing: Unknown error. Sync will automatically retry this action.

  • 11 replies
  • 38 have this problem
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  • Last reply by TheLovely

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Hi, i have just recently started having an issue with Sync on my desktop. My associated Android and Mac Laptop do not experience any issues when attempting to sync, but the desktop constantly gives the same error. I have tried unpairing the desktop, clearing all files, restarting and then adding the desktop to sync once again, but the error persists.

All of the bookmarks on the desktop have vanished, but are still in my sync data and have no problems being viewed on the other paired devices. This also tells me that the issue isn't the sync server and is something unique to the desktop machine.

I am hoping that this won't require a reinstall, but if all else fails, it is an option. I will try to attach a log file once i have submitted the question.

Hi, i have just recently started having an issue with Sync on my desktop. My associated Android and Mac Laptop do not experience any issues when attempting to sync, but the desktop constantly gives the same error. I have tried unpairing the desktop, clearing all files, restarting and then adding the desktop to sync once again, but the error persists. All of the bookmarks on the desktop have vanished, but are still in my sync data and have no problems being viewed on the other paired devices. This also tells me that the issue isn't the sync server and is something unique to the desktop machine. I am hoping that this won't require a reinstall, but if all else fails, it is an option. I will try to attach a log file once i have submitted the question.

Modified by nightech

Chosen solution

I believe that the error message is in the title of the thread:
Sync encountered an error while syncing: Unknown error. Sync will automatically retry this action.

Try to create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

Read this answer in context 👍 8

All Replies (11)

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Hi nightech,

You forgot to include the error message that you're getting on you desktop. Could you quote or paraphprase the error message you're seeing on your screen?

Thanks!

- David

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Chosen Solution

I believe that the error message is in the title of the thread:
Sync encountered an error while syncing: Unknown error. Sync will automatically retry this action.

Try to create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

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Thanks cor-el, I actually did just that last night and it has worked. I also did try the tutorial on deleting a corrupted bookmark file, as I had noticed I was unable to add new bookmarks even after removing sync from the profile. This however was not successful.

While it is an inconvenient solution (having to set up a profile all over) it has worked so far. I followed the instructions in the first link you provided. It only took about 15 minutes to create the profile, enable the addons and resync all of the data, and i really didn't need to manually copy anything over.

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

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This Sync Error looks to be pretty common. It's hit me the last couple of days and is a pain. I googled "sync encountered an error while sycnchronising. Unknown error." and found a forum post which advised logging on the the Mozilla account services and clearing sync data. So I do that and get the error "We had a problem purging the data from your account. Please try again later. " Ho hum. Creating a new profile and reinstalling a shedload of addons (I'm a web developer) is not appealing, so I'll just disable Sync for the time being and use old-fashioned offline backup methods until a more sustainable solution to the problem appears .

What I would suggest is that the error log be made available to users who want to see it. It's very frustrating to be confronted with "unknown error" or "there was an error" without being able to see the error to try to diagnose it. This can lead to high blood pressure and keyboard abuse

PS: I did a Firefox reset, reinstalled my addons and reconfigured my prefs, and the Sync error persists. Maybe it's a corrupt bookmarks file, as some threads suggest, but as there's no longer a single bookmarks.html to delete it looks like I'd have to delete the default profile. Where are bookmarks stored this days anyway? Not in the FF installation folder, and in the profile folder buried away in C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles\ there's only a bookmarkbackups folder full of JSON files that I can see - is that where they are?

Modified by fredriley

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Thanks, cor-el, that's helpful, and it explains why logging is off by default. I'll stash the link away for future reference.

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I'm having the same "Sync encountered an error while syncing: Unknown error" and even setting up a new account did not work.

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Sync dumped all my bookmarks. I had them on 4 computers. The last one I told it to merge the local with the sync data and it dumped it anyway.

I have tried recovering it and using one of the old Json files. I am in big trouble if I can't get these back can you please help me !.

DW

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If a recent JSON backup doesn't restore them then you need to try an older JSON backup in the bookmarkbackups folder until you find one that works.
The file size and file date should give some indication.

You can use this button to go to the Firefox profile folder:

  • Help > Troubleshooting Information > Profile Directory: Show Folder
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If by restore you mean go to: show all bookmarks then import and backup>restore> then pick a date in the drop down I have pretty much tried them all. They are all about the same size 469kb (which I take as a good sign).

When I choose a date there is no response it absolutely ignores it. I have tried this on all 5 computers. 1 is a lap top one is at my office and 3 are at home so they are not even connected except by sync. Based on this I believe (hope) that sync has an issue, but there is no internet "play" on it. Why else would all 5 not restore?

I have one older computer at home (#5) that I have forgotten about it was on and I looked yesterday and the bookmarks were there. I went to :tools>sync>manage acct>reset sync> and chose to merge that computer with the sync data and it....wiped out the bookmarks. The last place I have them is on my phone (told it not to sync) so I can at least copy it one by one.

Also: If I go to the address bar and type something like Charter cable (which I know is in my bookmarks) it comes up with a gold star and it show the description that I had in the book mark (because I will put in my account name as a reminder) so the bookmarks are in the machine somewhere !!!

Cor-el you have almost 8K solutions - If you can help me get these back you will achieve god status in my eyes as I do not want to have to re-set up the probably 1700 bookmarks I have (that is what it says when I say to wipe them out - which I don't do)

One more thing. I am not a real knowledgeable user. I can do as I am told and I am not a fool, but please use step by step instructions and small words.....

DW

Modified by DanwatkinsPER

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I agree. Too many issues lately with sync errors and flash crashes. I'm going back to Google Chrome for a few months. Don't have time to be bothered with the nonsense and slow fixes.