Firefox Sync troubleshooting and tips

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If you've run into a problem 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 change my password? (below)
  • Your Sync Key is incorrect. See Sync your Firefox bookmarks, history, passwords and more
  • If you've set a master password and haven't unlocked it
  • The Sync servers are under a heavy load - in this case, the error will stop when the server load returns to normal.

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 Beta 8, Firefox 4 B3 for mobile, or the Sync extension to version 1.6, 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.

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

Where can I find the code to add a device to Firefox Sync?

Where can I find the code to add a device to Firefox Sync? shows you how to find the code on a mobile device, an iPhone and another computer.

What is a Sync Key and where can I find it?

See Sync your Firefox bookmarks, history, passwords and more

I've lost my Sync Key, what can I do?

If you don't have a copy of your Sync Key saved anywhere and want to use Sync without creating a new account, you can generate a new Sync Key.

Warning: This will erase all of your data stored on the server. New data will be secured by this key and then uploaded. Your other devices will stop syncing and have to be re-added to your Sync account.
  1. Click the menu button New Fx Menu Fx57Menu and choose Options.Preferences.
  2. Click on the Sync tab.
  3. Click Set up Firefox Sync and a new window will open.
  4. Under I already have a Firefox Sync account, click Connect
  5. Click I don't have the device with me
  6. Enter your account email address and password
  7. Enter some characters in the Sync Key section (it doesn't matter what you enter)
  8. You will see a notification that your Sync Key is wrong. Click the new link that appears - I have lost my Sync Key
    Lost Key 1
  9. A new window will open displaying a Sync Key - ignore that and click Generate
  10. A new Sync Key will be made for you. Please take a moment to print it out or save it on your computer. Then click Change Sync Key
    Lost Key 2
  11. You will see the Setup Complete screen. Click FinishDone to close the setup window and take you back to the Sync panel.

How do I change my password?

  1. Click the Firefox Account icon in the toolbar.

    syncavatar logged out
  2. Click Manage Account.
  3. On the Firefox Account page, click Change next to Password.
  4. Follow the steps to enter your old and new passwords, then click Change to finish.
  1. Click the menu button New Fx Menu Fx57Menu and choose Options.Preferences.
  2. Click the Firefox Account tab on the left.
  3. In the Firefox Account panel, click the Manage Account link.
  4. On your Firefox Account page, click the Change… button next to Password.
  5. Enter your old and new passwords in their respective fields and click the Change button to finish.
  6. Close the about:preferences page. Any changes you've made will automatically be saved.

Check to see if other extensions are interfering with Firefox Sync

  1. Follow these instructions to disable all extensions except for Firefox Sync.
  2. 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.