To downgrade to Firefox 3.6 first uninstall Firefox 4, but do not select the option to "Remove my Firefox personal data". If you select that option it will delete your bookmarks, passwords and other user data.

You can then install the latest version of Firefox 3.6 available from http://www.mozilla.com/en-US/firefox/all-older.html - it will automatically use your current bookmarks, passwords etc.

To avoid possible problems with downgrading, I recommend going to your profile folder and deleting the following files if they exist - extensions.cache, extensions.rdf, extensions.ini, extensions.sqlite and localstore.rdf. Deleting these files will force Firefox to rebuild the list of installed extensions, checking their compatibility, and reset toolbar customizations.

For details of how to find your profile folder see https://support.mozilla.com/kb/Profiles

Finally, i am going back to IE. I have not used IE for years and have been recommending Firefox to people. I work in IT. but the new update 4.0 is really very very bad. I used to like it a lot. but i really do not know what the designers are thinking when working on 4.0.

Good luck with you guys.    this post is sent from IE.     it is sad to see FF going down the toilet.

myself was a FF user for last 12 yrs !! even i remember recommending ppl abt it...but FF 4 is a real PAIN IN THE APPROPRIATE PLACE....

it hogs memory...for simple functions (available by default in previous vers) ,now u have to install add-ons for them (like new tab button, FF4 either lets u have a new tab button OR the "+" button near opened tabs..but U CANT HAVE THEM BOTH SAME TIME!! WHAT THE.......

PC hangs/freezes almost everytime i ran FF 4 ..and for that i have lost valuable data..mind u, my machine config is not outdated. I have reverted back to previous vers FF 3.6...and am NOT UPDATING IT SOON....

ALL OF U FOLKS HAVIN PROBS WITH FF4 : easiest solution for all your probs -

1) get rid of FF4 and install the previous vers - http://www.mozilla.com/en-US/firefox/all-older.html after backing up - https://support.mozilla.com/en-US/kb/Backing+up+your+information

OR

2) get an alternative browser

yes folks, the above solution will at least give u peace of mind and a more peaceful good night sleep

Thank you very much for the instructions. The 4.X FF is REALLY bad...it almost made me resort to Safari. What I missed most was the "recent history" arrow placed directly to the right of the forward/backward arrows. One of the most convenient features.

Get your act together, FF.

I did just the same. using 3.6.17 now, no problems. FF4 is a disgrace.

Have version 3.6.11. Lots of websites I go to FF abrupty closes. No message, no error, just instantly closes. This is very crappy software. I'm probably like a lot of people, we switch browsers because the one we're using stops working correctly (and no I do not install crap). IE starts with the back button not working all the time so swithc to FF. Then after a few months FF starts crashing or freezing ALL THE TIME, but luckily IE has a newer version that works again. and the cycle starts all over. Is there a browser that is solid? I never checked out Chrome or any other ones.

3.6 doesn't help. Firefox is a piece of crap software. Last time I will try it. Now it keeps closing abruptly on many different websites. No add-ins, no warnings, no errors, it just closes all of sudden while you are browsing. And on the same sites each time. Yes I know I should spend hours reseaching on how to get firefox to work out of the box. No thanks. They suck. Tired of all the problems. I won't be messy with is crpaware anymore.

YEP! I'm going to find another browser. Firefox completely suuuucks! I am very disappointed. Later!!!!

Firefox used to be a great browers up until 3.6.xx -- I'm now on version 6.0.2 I have been patient since version 4, but sadly I am about to change browsers. I'm not sure which one though, both Chrome and IE-8 have annoyances... duh the fastration...

My main complaint is cache issues... Firefox does not refresh (F5) like it used to, and like other browsers do. As a web designer and developer Firefox was the best browser to work with (especially with Firebug plugin) ... Now it is painful to work with....

I have just come a new problem whilst doing some SEO work and it has totally caved my head in I'm so baffled - --- Firefox is showing different search results on Google to my other browsers. I have gone to tools >> clear browser history & have cleared all the cache and I have even rebooted my router (optained another ip suspecting this is a google thing??) I purged everything I can - yet the Google results are the same; which is different to the other browsers - so friggin weird!!!

BTW, http://support.mozilla.com/en-US/questions/726790 ?? is closed??

Amazing how Mozilla took Firefox from being the best browser to being the worst.

I just spent half an hour trying to remove the Yahoo! toolbar crapware from the browser and finally decided to uninstall Firefox 7 itself.

How could they make something so simple be so difficult.

Performance with add-ons has gone down the toilet, too.

I had FF 4 running fine with all stuff to stop it being stupid, then one day stuff just started stop working on it.And this seems to be after the new releases of the new crap versions of the now crap firefox.Its like Mozilla started stopping it functioning somehow remotely.Clearly Mozilla has been infiltrated by paid shills designed to destroy FF and promote Google SpyChrome.I will NEVER install Google SpyChrome.But other than using FF 3.6 Firefox is dead.

Paid Shills infiltrate the Organization in order to destroy it.

Yes its a SpyGoogle thing, Google has just gone completely insane and now hijacks everyones browsers and is officially spyware.But no one seems to mind about this.Probably PAID to shut up.

I was hoping the latest update was a new and better firefox but not today. I have been using Google Chrome and at least it has been working although with a glaring problem, after you run several flash video's it will crash hard requiring you to exit all Chrome windows. I hear a new IE is out so looks like it will be trying that out. I never found a reason/fix for FireFox abruptly shutting down. Even after an uninstall/install, it still did the same thing. It is so odd that Firefox is going from rock hard stablility to piece of crap and doing nothing about it.

I'm really starting to lose faith in Firefox. Ever since I went to version 7, it's multiple cases of freezing every day. This has gone on for a month now. This usually deals with switching tabs or a site with Flash on it. I downgraded to 6 and the stability problems were fixed. The next time I restarted, I was FORCED to upgrade to 7. Now it's back to regular freezes. For years, Firefox was the shining example of what makes open source great. As a web developer, FF is the baseline standard for display and functionality due to Firebug and the best for sticking to standards. I've sung the praises of Firefox, but it's getting harder and harder to do with the ever present unstable piece of Crapware called FF7. Whatever "security fixes" were implemented are at the expense of a stable browser. I've turned off all add-ons and hardware acceleration. Same result. Frozen Browser. Unacceptable. I'm on Windows 7 and I've had it happen on my Mac at home. If every time I have to kill the firefox.exe process results in a "Well this is embarassing..." message, why hasn't this been fixed yet? In the past problems were usually addressed right away.

@reddog: Re-"Is there a browser that is solid? I never checked out Chrome or any other ones."

I do Not recommend Chrome. It installs a lot of other background programs that can slow down your system. The worst part is they don't let you know they're installing all that background crap, which is what I find despicable. Of course, they claim that you can always uninstall and reinstall w/ Custom settings... (blah, blah, blah... whatever).

Honestly, I don't think there are any good browsers out there anymore (unless FF v.8 gets fixed).

I wish there were something out there that was focused on people being able to enjoy using the internet without being bombarded with useless, bloated features. Perhaps something that also isn't susceptible to all the viruses designed for Internet Explorer. Something that lets you set things up how you like it, and doesn't constantly force new features on you, so you don't have to keep re-learning how to use your browser (and respecting the fact that you have better things to do with your time).

Hey, wait! There Was something like that a long, long time ago. I think it was called Mozilla, or something like that. What ever happened to them? I wish they were still around now...

Hey Mozilla! Your Firefox is crashing more than a severely retarded racing car driver who has just been blinded by the sun. What the hell is going on with my favourite browser?!

I hope you fired the delinquents responsible for this update because it's this kind of thing that has helped to knock Firefox off the top as the most popular browser in the world.

So it's minimalistic Chrome for me now, although I won't have a choice but to test code with all browsers including Firefox.

Please fix this mess.