If you've run into a problem while trying to sync with Firefox Sync, this article will walk you though the most common solutions.

Error While Syncing

There are number of things that can cause this:

Your Sync client isn't compatible with the data you have on the Sync server. See I upgraded something and now Sync doesn't work (below)
Your password is incorrect. See How do I choose what types of information to sync on Firefox?
Your Sync Key is incorrect. See Sync your Firefox bookmarks, history, passwords and more
You've set a master password and haven't entered it.
Ths Sync servers are having issues to handle your data. In this case, see ‘’’Resetting my account’’’
The Sync servers are under a heavy load - in this case, the error will stop when the server load returns to normal.

I use the Firefox Sync add on and something doesn’t work

Since we launched Firefox 4, Sync is now part of the browser and the add-on is no longer needed. The add on will keep being active causing some misbehaviours, like not handling properly the tabs opened in a different computer. We recommend you to disable it. You can find detailed instructions about how to do it in Disable or remove Add-ons.

Resetting my account

In some cases where you are getting regular errors and restarting Firefox or waiting doesn’t solve the issue you can try to reset your account and upload fresh data to your sync account. In order to do so, see Replace your Sync information.

I upgraded something and now Sync doesn't work

We recently changed a lot of things about how Sync works. One of those was the way it stores your information. If you've updated one of your devices to Firefox 4 or Firefox 5, or the Sync extension to version 1.7, your Sync data has been updated to the new format. This means that any of your other devices which have not been updated, will need to be updated in order to keep syncing. *Firefox Sync add-on page (for Firefox 3.5 - 3.6)

Note: After updating, you may need to connect your device again. See How do I add a device to Firefox Sync?

Check to see if other extensions are interfering with Firefox Sync

Follow these instructions to disable all extensions except for Firefox Sync.
Then test for faulty extensions.

This didn't solve my problem - I still need help!

If you're still having problems with Firefox Sync, please try asking your question in our support forum.

Firefox Sync troubleshooting and tips

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