Sorry you're having a problem with Sync. Let's get some important details out of the way.

Did you try what was suggested in that other support question thread? "log out of sync and try to reattach the account, but before you do, rename the device to something else."

Sync Setup let's the user know when the initial Sync is completed be showing a message like Sync Complete. Depending upon the amount of data being sync'd, the load on the Sync servers, and the speed of the internet at the time of the initial Sync it could take some time to complete. Personally I have seen it take 45 min to complete the initial sync with a new account, when there are like 3000 bookmarks involved and browsing history is selected. And with 100's of tabs in session history or a lot more bookmarks it could take a couple of hours - I guess. I ran out of email addresses to use when testing Sync back in 2011 with the previous version of Sync in Firefox 4.0 to see what more I could learn about it after it was made a standard part of Firefox. I was using 3 Sync accounts when Sync was offered as an extension / addon service.

Even if the initial Sync wasn't complete, I would expect that you would have gotten at least some data back. But I can't say for sure - I have always let a new account initial sync run until the completion message appeared.

1. Sync wasn't intended to serve as a "cloud backup" service - it is intended to synchronize Firefox user data between multiple devices. As guigs2 mentioned in that other thread, when she asked about that user having a backup of the Profile folder.

2. Using Sync as the only data backup when formatting, although not supported, can be made to work - but most of the users we see posting here with problems when using it for backup all seemed to have made the 'fatal' mistake of requesting a new account password. When doing so, all the user data for that account is wiped from the Sync server for 2 reasons; it allows the user to start anew with Sync while using the same email address, and the account password is used to create the encryption "key" that protects your data when it is off of your devices; in-transit and when on the Sync server. Without the correct "key" your data is useless, it can't be decrypted when it gets back to your device. Overall, that level of encryption isn't needed for stuff like like bookmarks and browsing data - but it is the way it is.

Thank you for your reply.

Renaming the device didn't solve the problem.

I had only a few bookmarks (100 at most) and I'd say about 30 passwords saved.

Also, I've never seen any message or any kind of feedback from Sync whatsoever. I just assumed it was working properly. AFAIK you don't have access to any information regarding Sync: you don't know if it has uploaded or downloaded data, you don't know anything about the data that's on the cloud. It's a 'blind' functionality, there's nothing you can do but to assume it's working properly. It's extremely frustrating when you hit 'Sync' and nothing happens, there's a message that Sync will begin to work momentarily after you logon but that's all. I've never noticed any other information.

I think there's no way to know if my data is saved other than manually taking a look at the DB to see if there's some data there.

The problem with backups is that recently FF has some problems that seems to be related to the way it saves data... It gets very slow and even after reinstalling everything, if you just copy the data directory over the new install will get slow also. Even resetting the settings doesn't seem to work properly. In this case FF was very slow and some functionality were broken, for example on some sites I couldn't change the language (even on safe mode). So Sync was the perfect solution to backup only some important data and retrieve it in a 'vanilla' install. I rather not use third party software to backup my passwords.

I've never requested a new password.

Yes, "feedback" to the user is scant. The entire process is designed to work without user intervention. But there is a "Sync Complete" message that appears when the initial Sync for each device is completed. And if the Sync button is placed on a toolbar, the tooltip will show when a "Sync process" was completed. But that's about it for "telltales".

Sorry for your lost data, but Sync just wasn't made for the purpose you used it for. A manual backup of your Profile folder would have been the way to do it. Then you would have had the option to restore your entire Profile or restore specific files, like the 2 or 3 for your Passwords. And the places.sqlite file with your bookmarks and browsing history or a bookmark backup file alone.

Thank you the-edmeister, I suppose you don't have access to the Sync database, in this case we're both assuming that the data was lost. I really should've backed up the profile folder just in case, so it's partially my fault. I'm a little disappointed though. It was certainly not a pleasurable introduction to the Sync technology. I use a similar technology in another browser and I must say that FF's Sync is really lacking behind. In the competitor you can see what is on the cloud -what's relieving when you're not sure what is going on- and so far it worked flawlessly. I like FF better than the competitors though and I'm around since the Netscape days, so I'm a kind of a fan, but lately FF has been a major source of frustration in my life :). It's not only the Sync, I didn't like the new UI and many other things they introduced recently.

I hope in the future FF not only allow you to see what's in the cloud but also provide a way to backup your data (allowing you to choose exactly what you want to backup, perhaps exporting it to a single file that you can easily copy somewhere else and import on another system, or even backup in the Sync's cloud itself).

I appreciate your help, thank you very much.

Sorry to bump this, but for some reason Sync is not working for me.

I've browsed some websites and then sync'ed, I've waited for the spinning anim and confirmed the last sync time by hovering the sync icon, then I've removed the folder %appdata%/Mozilla/Firefox, launched FF, signed in with my Sync account, but when I sync nothing is retrieved, hovering the Sync icon it says it was sync'ed but there's nothing on the history, saved passwords, bookmarks, etc.

I've repeated this a number of times, always making sure that all checkboxes are ticked and it never works. I think there's a problem with my Sync account. I've tried different device names just in case.

Update: It seems Sync started working... I think I lost what I had before it started working but it wasn't important. I can't rely on it though.

http://idioms.thefreedictionary.com/watched+pot+never+boils

Nice one the-edmeister.

It seems to be working consistently now, the only thing that isn't syncing are the tabs but I think that's the intended behaviour (when you have tabs open and sync for the 'first time' the tabs will 'override' the ones in the cloud, it would be better to ask for which tabs you want to keep, but that's very minor).

I hope it works from now on, but I'm not going to count on that next time. I still think that a proper way to know what's happening is much needed though. It shouldn't be too hard imho to code a better 'manage account' page that just shows you what's on the cloud (just the number of each kind of data is enough). At the moment that page only has the 'change password' and 'delete account' links what's better than nothing but too much basic imho.