Disable Firefox Sync on a lost phone or tablet

So you've just lost your device (sorry about that) and you realize you've been using Firefox Sync to get all of your usernames and passwords on it. This article describes what you should do to prevent someone from accessing your passwords on your lost device.

First, change your sync password from a synced computer

This first step will prevent your lost phone from connecting to the sync server and getting all of the new passwords that you will have to create in the next section.

  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 select 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.

Second, change all of your account passwords from a synced computer

It's important that you change your sync password before changing your other account passwords so that your lost device doesn't sync your new passwords.

This part is more time consuming but important. If you don't change the passwords for things like your bank account, it would still be possible for someone else to log in to your account on your lost device.

See Create secure passwords to keep your identity safe for an easy way to create better passwords.

If you've set a master password on your other device and you didn't leave Firefox open, you don't need to do anything else.
// These fine people helped write this article:Tonnes, Michael Verdi, scoobidiver, Swarnava Sengupta, jtsmith73, pollti, Joni. You can help too - find out how.

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