A couple of options, you can reset the sync key which will delete the details on the Sync servers allowing you to start over again. For details of how to do that see the Firefox Sync troubleshooting and tips article.

The sync key should be stored in the password manager of the Firefox version that you originally set up Firefox Sync with. Open the Options/Preferences dialog (for Windows, in the Tools menu select Options). In the Options dialog go to the Security panel and click on the "Saved Passwords" button to open the password manager. In the password manager click on the "Show Passwords" button and in the search field type chrome, that should show your sync key.

Thank you for your prompt reply!

The sync key is not with me in any case, since the backup operation I did was extracting the image of the system 5 months ago, long before I set up Firefox Sync. As a result, there is no saved sync key.

When I get to the Sync tabs, I couldn't see the interface mentioned in the article as from Firefox point of view, I haven't set up Firefox Sync. However, as stated earlier, I already one under my email tonghuukhiem@gmail.com and this prevents me from setting up another one.

Hope these screen-shots can further clarify my situation:

http://farm5.static.flickr.com/4085/5067108479_e31fd1972d.jpg

http://farm5.static.flickr.com/4152/5067108483_4647a9699a.jpg

Try logging into your account, when it asks for the Sync Key enter some random text and it will inform you that the Sync key is wrong and give the option of resetting the Sync Key, you will lose any saved data on the servers.

Thank you, the problem has been resolved

Except that it will delete everthing... incredible! please explain things properly. I'll move to Chrome after this armful trick from firefox. Thanks!

You missed this warning.
"This will erase all of your data stored on the server. New data will be secured by this phrase and then uploaded. Your other devices will not be able to sync until this new Secret Phrase is entered for that device."
about halfway down this page
https://support.mozilla.com/en-US/kb/Firefox+Sync+is+not+working

The data is encrypted on your computer with the sync key before it is being uploaded to the sync server. So if you lose that sync key then data stored on the server can't be decrypted anymore and becomes useless. If you create a new sync key then all old data needs to be removed and you start with fresh data. It is the same as the Master Password for storing passwords. If you forget the MP then also all stored passwords can't be decrypted and are lost. So make sure that you keep a copy of the sync key in a safe place.

• https://wiki.mozilla.org/Labs/Weave/Crypto

yesterday, 2 guys got into my house (while i was inside) and they took everything. Including both computers i got synced. Now i'm trying to recover all my firefox data and its asking for a sync key. WTF !!! isn't it possible for them to send it to my mail ?? why would you need that.. i already have a username and pass... any way to bypass this or i'm just going to loose years and years of history and password just because someone invented a sync key that con only be reset while erasing all my data ?

The SyncKey isn't saved anywhere except for your PC's that are setup for Sync.You should have made a copy of the SyncKey and stored it in a safe place. Mozilla doesn't have your SyncKey, so they can't email it to you.

I tried to do as suggested before to reset my sync key (I cannot even remember when I DID set up firefox sync, but it says I already have a sync account, so whatever) but it doesn't give me the "I have lost my sync key" link. So now I'm stuck and cannot do anything to fix it.

Hi,

I realized that creating a new sync key erased my data. Would it be possible at all if I found my old sync key to restore a backup of my database? It would be awesome if this could be done. May someone please, please look into this?

Btw, I actually appreciate the whole sync key thing. It give me a level of assurance that my info is private and not roaming around.

Thanks!

If you have created a new sync key for that account then all data that was stored previously has been removed and can't be restored. If you created a new account then the old account should still have that data.

Ok, thought I'd give it a shot! Thanks.

Wow! All web passwords are there for anyone to read that sits down at your computer? I didn't expect high security but I certainly didn't expect plain text with no security at all.

See:

• https://support.mozilla.com/kb/Protecting+stored+passwords+using+a+master+password

OK. I know u have this problem and this your awnswer. Go on firefox->got to options->go to sync tab->manage account->sync key and tada!! There u have it. Hope that helps