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Firefox sync fails to sync and produces error logs in about:sync-logs

  • 8 replies
  • 8 have this problem
  • Last reply by cor-el

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Hey there, I have been having problems with Firefox Sync for about a year now, and I have been trying multiple things to fix it, but I finally sat down this weekend to try and fix it, but I am still having issues.

I have 4 Firefox installations: 3 PCs and 1 Android

For a while, all of them were failing to sync; I reset all of my sync links multiple times, cleared my sync data multiple times, and even created a new profile or two to no avail.

This weekend and I recreated every single profile from scratch and had them download what was in my sync profile. Now 3 out of my 4 profiles seem to be sync'ing properly, but my last one at work is still not working properly, and I am getting errors in the about:sync-logs section. I have even tried sync'ing in safe mode but to no avail.

I have captured some of my error logs, which can be viewed here:

Any help is greatly appreciated!

All Replies (8)

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Ah you need to add the recovery key to the device that is not working. If you have that use it to re add the problematic device.

Please let me know if this works, we are happy to further assist.

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I'm curious as to how the Sync would be set up without the recovery key, I thought you either had to enter it manually, or it was retrieved automatically with the "Pair a Device" feature.

A little more information; If I remember correctly, (I reset my profiles like a half dozen times, so I think I'm remembering correctly) in my frustratation to get Firefox Sync to work, the first 3 devices (two PCs and an Android), I did not use the "Pair a Device" feature, I did the manual login + recovery key.

However on my 4th installation (the one with the most problems currently), I used the "Pair a Device" feature to skip the hassle of looking up my recovery key. I looked at the "My Recovery Key" section, and the key is properly listed there, so I don't know why my log is spouting issues about it not being there. I'll take your advice and re-link the profile and do it the manual way.


Ok, I tried re-linking the profile with the manual login, but it still failed. Here's the sync log that was created as a result of the failure:

Modified by CGar

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What stood out in the sync log was the DEBUG notification where there is no recovery key.

Sequentially, it looks like it logs in, it completes the sync and sets the next sync for 36000 seconds.

then it has no sync key value

1390407480214 Sync.Identity INFO Sync Key has no value. Deleting. 1390407480214 Sync.Status DEBUG Status.login: success.login => error.login.reason.no_recoverykey 1390407480214 Sync.Status DEBUG Status.service: success.status_ok => service.client_not_configured 1390407480214 Sync.Service INFO Logging out

then is failes to reconciles some of the records, there are about 7 of them, 1390407483369 Sync.Engine.Forms WARN Failed to reconcile incoming record +UIQBcVnQ421yL/5

If this happens again with the same steps

  • Go to about:config, find

services.sync.log.appender.debugLog.enabled and set it to true, then restart.'

One thing I noticed is that you are using an old release of Sync, if you go here you can detect if you have the latest.

I also found the life of a sync -which is really old but it gave a hint that there are records that exist with the account detected an then it resyncs after setting the sync time after a partial error. Note this information is incomplete, this is just a hypothesis.

Anyway, a fresh start is recommended, pairing a device with one primary device(it will always be the first device you sync) and the recovery key is used for recovering which makes me think that Manual login + recovery key is detecting the recovery from one of the initial syncs? Do you have more than one recovery key?

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Firefox stores the name and password and the sync key in the Password Manager.

Do these entries still show correctly?

  • Tools > Options > Security: Passwords: "Saved Passwords" > "Show Passwords"
  • chrome://weave (Mozilla Services Password)
  • chrome://weave (Mozilla Services Encryption Passphrase)
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On my last few logs I don't seem to be getting the sync key error any more, but there are still some failures to reconcile records.

The about:config key for

  • services.sync.log.appender.debugLog.enabled

did not exist in my configuration, so I created the boolean key and set it to true, restarted, then sync'd.

The following debug log was produced:

I went to the website that you directed me to, and it reported that I was using an out of date version of Sync. I tried installing the version it provided and restarted; the add-on showed up in my add-ons list, but the website still reported I had an out of date version of sync. This add-on also failed to let me view my tabs from other devices, so I uninstalled it.

I found this to be an odd request because if I remember correctly, the Firefox Sync add-on was deprecated in favor of the built-in version.

@cor-el I checked those password entries and both of them are correctly displayed.

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Hi ChrisG683, There has been a remodel of Firefox Sync that is available in Firefox 28, atm Aurora. It is kind of cool, I just send the screenshots of it to the content manager, so you will see it at the end of the next release cycle. I am really sorry for the inconvenience. I will also follow up in you other question here

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Oops, I accidentally marked it as solved when I didn't mean to. I have tried the new Sync in Nightly, but I still have the exact same problems.

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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 cautious not to copy corrupted files to avoid carrying over the problem.