Firefox Sync is NOT A BACKUP SERVICE. It was not designed to be one, nor does it function like one. There's not necessarily a permanent or complete copy of your data on the Firefox Sync server.

Additionally, some account actions (like changing password) cause the Firefox Sync data to be erased.

If the data does not come back when you log into Firefox Sync, try disconnecting and connecting to sync again.

If it still doesn't come back, it's likely that the data is not actually stored on the sync server anymore.

In that case, you will need to recover the data from another device that has the same data.

I never mentioned anything about a "backup service", nor did I assume one. But if sync doesn't function, like it is supposed to, then what is the point of even using mozilla? There are better browsers with backup services.

This wasn't expected of Mozilla. Never in my history of using mozilla has this error ever occurred. There is no data. I've already re-installed mozilla twice, disconnected and reconnected it. Luckily I have a backup on my laptop, only thing is I have to manually restore it.

The best backup is brains, I visually remember all my bookmarks, but it is frustrating to say the least. Imagine what other non-It users will go through, if they come across this glitch. You will loose major customer base. Including me

Firefox Sync is designed to reflect changes to settings, bookmarks, history, etc to other devices that are using Firefox. It's not designed to rebuild all of your information if you erase it from your computer.

Did you or did you not reset your Firefox Account password when attempting to log into Sync after that re-format?

If your data is lost, I am sorry about that. And the latest "update" to Sync servers that could cause that was with Australis Firefox 29 when a new batch of "sync" 2.0 severs was enabled for a massive change to Sync login procedures. Later versions of Firefox all have worked well, so your issue isn't connected (IMO) to a Firefox update, period.

And yes, I have suffered the same loss of my data with Sync 2.0 - but I was prepared when transitioning to a newly built PC thru Sync; I had backed up my Firefox Profile to USB Flash Drive before using Sync. Once I realized what I had done, I plugged in the USB Flash stick to recover that data, saving me a trip into my workshop to the older, about-to-be retired PC to then copy my Firefox data.

The original password holds the "encryption key" for your data! When the password is changed the data which is held on the Sync server becomes worthless; even the IBM Watson supercomputer would be hard pressed to recover your data, and if it could the end cost would be phenomenal.

BTW, I am not an IT techie. I am a 70 yo computer user with skills gained over the years dating back to 1984 with an IBM-XT PC for my business and used that old XT PC (using command code to launch the software each day) until 1993, when my Shop Keeper software was being retired for an all new version for use with the first Pentium P-5 grade chips. $15,000 plus upgrade in those days for vertical market software packages, on top of the new computers which also had vastly improved networking between PC's sharing data.

Did you or did you not reset your Firefox Account password when attempting to log into Sync after that re-format? If your data is lost, I am sorry about that. And the latest "update" to Sync servers that could cause that was with Australis Firefox 29 when a new batch of "sync" 2.0 severs was enabled for a massive change to Sync login procedures. Later versions of Firefox all have worked well, so your issue isn't connected (IMO) to a Firefox update, period. And yes, I have suffered the same loss of my data with Sync 2.0 - but I was prepared when transitioning to a newly built PC thru Sync; I had backed up my Firefox Profile to USB Flash Drive before using Sync. Once I realized what I had done, I plugged in the USB Flash stick to recover that data, saving me a trip into my workshop to the older, about-to-be retired PC to then copy my Firefox data. The original password holds the "encryption key" for your data! When the password is changed the data which is held on the Sync server becomes worthless; even the IBM Watson supercomputer would be hard pressed to recover your data, and if it could the end cost would be phenomenal. BTW, I am not an IT techie. I am a 70 yo computer user with skills gained over the years dating back to 1984 with an IBM-XT PC for my business and used that old XT PC (using command code to launch the software each day) until 1993, when my Shop Keeper software was being retired for an all new version for use with the first Pentium P-5 grade chips. $15,000 plus upgrade in those days for vertical market software packages, on top of the new computers which also had vastly improved networking between PC's sharing data.

It's always a pleasure to learn from elders, because they always have skills that are wonderful. I have a complex password for my FF sync, and I have always been an advocate of 2FA. But in this case, let me assure you neither did I change the password, nor did I use 2FA from FF.

I had installed LastPass password storage manager a couple of months back, and everything seemed to work fine, I have even formatted my PC 2 months back, and restored FF, it was perfect. If you suggest that it has nothing to do with the update, perhaps I might beg to differ, because there is no other issue that I could have had.

It seems the only option for me is to restart my old laptop, and bring up FF, and export all my bookmarks, and logins. This should be a case study for Mozilla, as to what could have happened. I am open to more questions.

The original password holds the "encryption key" for your data! When the password is changed the data which is held on the Sync server becomes worthless; even the IBM Watson supercomputer would be hard pressed to recover your data, and if it could the end cost would be phenomenal. BTW, I am not an IT techie. I am a 70 yo computer user with skills gained over the years dating back to 1984 with an IBM-XT PC for my business and used that old XT PC (using command code to launch the software each day) until 1993, when my Shop Keeper software was being retired for an all new version for use with the first Pentium P-5 grade chips. $15,000 plus upgrade in those days for vertical market software packages, on top of the new computers which also had vastly improved networking between PC's sharing data.

I have a fair idea about encryption, and the robustability. My first ever PC was a ZX sinclair, then an Amiga 500, and so on. I should have taken up software programming, as I was good in coding games.

Ok so here is the scenario - I have successfully powered up my laptop with old FF data, and it is working fine. All bookmarks are there, but when I sync them, the changes are not reflected in my PC. I know how to backup, export etc, but if the sync isn't functioning this is a glitch in FF. Can someone explain?

Firefox Sync is designed to reflect changes to settings, bookmarks, history, etc to other devices that are using Firefox. It's not designed to rebuild all of your information if you erase it from your computer.

I understand, but it doesn't explain the question I just posted above.

I think the Sync service might be kaput for some folk. Pop about:sync-log in the address bar - do you have lots of "error-sync-*****" files?

I think the Sync service might be kaput for some folk. Pop about:sync-log in the address bar - do you have lots of "error-sync-*****" files?

Dear Mike,

It is full of errors. This is the first time I have used this command, thank you so much for pointing it out. I guess the problem is with Mozilla. Any clue if Mozilla is aware of this, or sorting it out? I've formatted my PC twice now, thinking there might be a malware issue, but this isn't the case.

How do I submit a bug for Firefox Sync?

For some reason, I logged in today, and everything was synced.

That's great news!

The main problem (there are several bad ones now, when there were few a couple of years ago), with the last three or four versions of Firefox is that it resets the user's FF installation to "factory settings" whenever the browser is updated or patched -- true upgrades seem to be missing these days.

I have yet to see a plausible explanation why the user's settings (everything that is wiped away to some location that requires the user to remember the Firefox login password and (probably) a master password. Even if the user recalls bother of those, someone blatantly decided to make it difficult for users to restore their old settings, when that should be a one or two click task at most. Any setting, bookmark, add-on, etc. that does not automatically get restored should throw an error message that explains at least roughly what went wrong and why (e.g., the AdsOff addon failed to load because it relies on Firefox(ignoring that functionality that has been removed for the following reason: "some vague excuse about security usually works here".

I cannot think of any quality product of any that has lots of settings, customizations, and modifications the user can select, make, or install that just throws them away willy-nilly whenever the Product is fixed or updated, even possibly improved. I suspect the reason I get no reply to this point is that someone would be embarrassed at the ineptitude of developers who are NOT working at Microsoft, a large government agency, or other organization where end users are paid almost no attention.

But even Microsoft strives to make sure that new releases of Office, Visual Studio, etc. are as seamless to the user as possible. I have worked on systems where the primary application programming language as well as the operating system itself were "under development" during almost all non-business hours. They were DEVELOPMENT systems that were run in "last stable configuration" during working hours. Current releases of FF have been far more user hostile.

Again, what is the excuse for not just simply giving users the option to run a newly updated release of FF, click the button to restore all the non-factory spec settings, addons, configurations, bookmarks, etc. they were using the previous day, then click the "Yes, I am damn sure I want to at least try to keep as many things the way I last had them set up."

 Interestingly enough, although I quit playing WoW about a month ago, Blizzard also had a "revert to default game UI -- no addons, a lot of settings undone, etc. -- and as the popularity of WoW was tanking, the WoW devs have made it possible to at least see all the addons one had, active or not, and try to load the custom set one last used.  There were warnings about how horribly wrong this might make things go, but I cheerfully ignored them and found it much, quicker, easier, and less painful to just disable addons that had not caught up to the newest WoW patch, tweak the settings of addons that still worked so they did so correctly again, and dealing with more subtle glitches that showed up over the next few sessions of game play.

 I cannot think of a good, plausible technical reason that Firefox updates and patches hve to wipe or reset all user customizations and make them a royal PITA to restore.

The real problem with Firefox's "password vault" for username-password combinations a user decides to let it save is that it is POORLY DESIGNED.  Human beings make mistakes.  People forget things.  People lose things (such as the sticky note under the keyboard where they write, in very tiny letters, all of their important logon info).  That is after they forgot that the first place any knowledgeable person looks for someone else's password cheat sheet is under the their computer keyboard or very near whatever device they normally use to access the internet.

 I have a simple solution for those like me who no longer trust Mozilla to provide a secure password vault that allows users to be human enough to forget things such as passwords.  Ideally, the password vault should not be part of Firefox in the first place, but rather one of the many on the market that will work with multiple browsers or no browser at all.  it makes me very suspicious that Firefox users are pushed hard to Sync other devices where they use Firefox.  

 I have no need to use Firefox Sync.  Anything I want to keep synced I can do wherever I have a computer with an Ethernet connection to the internet via a LAN I trust (more than a WiFi connection, anyway).

 Just to be sure: is there a valid technical reason why FF has to be reset to default configuration every time it is patched, updated, or upgraded(?).  Firefox was arguably my favorite Web browser of all time, until a year or two ago.  Were the devs who lost their jobs due to downsizing the sort who could take whatever challenges are involved in making the user experience of going through a new release of Firefox in stride without getting all stressed out about it?  

 Sadly, the most experienced, highly-trained, or talented developers often seem to be the first to be let go when organization downsizing is a must.  They generally have the best (if not golden) "parachutes" and often have no trouble ignoring NCAs if they are let go through no fault of their own (except maybe being so good they expect high pay), the top top technical talent being laid off or just leaving for much greener pastures.

 My solution for non-trivial browsing for purposes that require passwords will have to be one of Google's or Microsoft's products until something better, more reliable comes along.  It seems odd to me that Mozilla gets a huge amount of funding from Google (or some less well know part of Alphabet.  That would seem to suggest that Google needs to have competition in the browser marketplace (besides Microsoft which has caved in every way to Chrome (and Linux to an increasing extent) except for making a public statement to that effect.  Opera is a niche-market browser.  Whatever Apple's latest browser is called, it is unlikely to be used much or talked about outside of the Apple fanboy market -- which works just fine for Apple. :)

 Does not Google have some sort of conflict of interest in providing major financial support for Mozilla when Firefox is clearly cutting into Chrome's share of the market?  That is probably the most interesting and least argumentative question I have asked in this message with plenty of questions, actual and implied.

Regards, Mark

P.S. Sorry for not proofreading the above much. I hope to have one, maybe both of my spiffy gaming laptops back online by December 2nd. This Toshiba L505D-series laptop was purchased for someone else who did not expect to be using it much, but wanted a computer I could teach her how to navigate to and around few business, news, and investment sites she actually made good use of.

Hi Mark.

Firefox should not be resetting your settings when you update. In fact, that's actually probably not what's happening. It's more likely that Firefox is creating a new blank profile folder. The profile folder is what stores your user information.

There are a number of reasons why Firefox would do this. But for some reason, Firefox thinks that the update is actually a new installation of Firefox.

Fortunately, when this type of issue happens after an update, it's quite easy to fix. See Recover user data missing after Firefox update.