Firefox is highly customizable and you may be able to customize it to meet your needs.

If you do not like the new UI, you can make Firefox 4 look and behave more like Firefox 3.6, for details see http://redherring2.wordpress.com/2011/01/17/firefox-4-restoring-firefox-3-ui

If it is something else you do not like, what is it?

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

In fact,-you cant download any older version of firefox but google chrome:http://www.google.com/chrome Or Opera

[http://www.opera.com/]

"In fact,-you cant download any older version of firefox"

That is wrong, all previous releases of Firefox are available for download - ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases

it will not let you complete the download if you have firefox 4!!!

I downloaded 4 and HATED IT!!! So I found this link on the firefox website and am now running the previous version.

http://www.mozilla.com/en-US/firefox/all-older.html

Good luck to Firefox. My husband tried 4.0 for all of a day before giving up and switching to Chrome and we've been adamant firefox fans since it first came out. This new version... It's not working.

I love Firefox and have used it for many years because it's so intuitive and user friendly. 4.0, however, blows. It seems like there are too many changes just for the sake of change, minor little details that worked absolutely fine in every single version previous but, well what the hell, let's switch it around anyway just to confuse people. Why are the tabs in a different place? Is there seriously any advantage to that?

Why is the Home button clear on the other side of the screen? EVERY OTHER ASSET, the tabs, the bookmark toolbar, back/forward buttons, even the url bar itself is anchored to the left side of the screen, why suddenly segregate the home button? What genius assumed your users wanted to have to bounce back and forth across their entire screen every time they needed to get back to google?

Additionally, why am I suddenly prompted to restart in 32 bit mode every time I want to watch a video? And speaking of videos, why do several video formats no longer work? I can't get Hulu to play anything except commercials, it simply freezes on a blank screen when it's supposed to show the feature. I've updated Flash, I figured out how to make FF automatically start in 32 bit mode, I even disabled all my plugins and add-ons, but nothing fixes it. I never had these problems with 3.6 and honestly it's not with acclimating to an annoying new layout just to get a browser that's apparently so flawed.

If it's not broken don't fix it, mozilla.

Fix the crashed !! Firefox shouldn't crash, as we always know it, the new version (4.0) is very slow and always crashes and take a huge amount of the RAM !!! I absolutely HATE it too !!!

I got sick of Firefox 4 and downloaded Firefox 3 from http://www.oldapps.com/.

FF 4.0 absolutely unuseable for me and for my wife as a college student. The college uses Firefox for their online classes. All students were warned not to upgrade to FF4.0. To get rid of it first uninstall it FF4.0. Then go to http://www.mozilla.com/en-US/firefox/all-older.html Then select your language, which in my case is English US. BTW, I used Internet Explorer to download Firefox 3.6.16.

I installed FF4 & hated it so much that I uninstalled it. I need en-gb version of FF so I can`t use FF to download my previous version. I found 3.6.15 in my download list & re-installed that although I`m sure I had 3.6.16 before.

If 3.6.15 is satisfactory I`ll be leaving Firefox. FF have made a big mistake with FF4.

I absolutely hate the new Mozilla Firefox vs 4! I love the new cartooning look, but the old format/layout of Firefox needs to come back! I HATE that the tools (file, edit, ect.) are gone and nowhere to be found! I HATE the bing thingy! I have blocked, changed the homepage option to www.google.com and it still shows that blasted bing search bar! I find Bing offensive just by the look of it! I have been reading and apparently people are having hard time getting rid of bing. I uninstalled it and then deleted it from my files and did a complete clean up and then I update Firefox and then BAM! It's still there!!! Apparently there is a drop down menu next to the bing icon you can change. But I wonder just how long until you have to change it back! Also, I want the old Mozilla homepage with Google search bar!

I have been using firefox for years with no issues for my web business. Two days ago it updated itself without my approval and now all Wordpress sites I try to visit and all the ones I manage will not load , and if they do they will not save data. It really makes me so sick and migrating to another another browser it not an option ... They have to fix this issue...

Since I have to use a IE clone, I might as well use IE. Really should have an option somewhere to have a classic view. Not even Microsoft was crazy enough not to offer that when they completely changed the interface. People don't like change, especially with something they are VERY comfortable in using. I'll try some of these links up here, but would feel better if it came directly from mozilla's main page so I'm not worried about downloading anything like spyware/viruses posted by people I dont know.

My biggest gripe is with the COLOR and POSITION OF BUTTONS on the navigation bar, specifically:

BACK/FORWARD button REFRESH button HOMEPAGE button (mine’s set at Google)

I want them restored to their original easy-to-see position and colors: RED, GREEN, BLUE and Google’s YELLOW-house icon. (Not even sure red and green were there since I can’t remember my beloved Firefox 3.6 nav bar anymore. Cripes!!!)

FREAKIN’ ANNOYING !!!!!

If I wanted Explorer, I would use Explorer and not add Firefox. This needs to be reversible quickly, and easily enough for those of us who are not tech-savvy. There are so many reasons to HATE this new Firefox I wouldn't know where to begin!!

Thanks to the smart people who put up "fixes", but I'm not going to spend a whole day figuring out how to mess with all this. Either Mozilla wants a broad base of users (we ancient relics buy a LOT for the target age-groups and the grandchildren) or not. I'll just go back to Explorer, since I now hate them equally!

Thanks to someone showing me how to change Firefox 4, if I wanted Chrome -- I would use it.

Sill a few things about Firefox 4 I don't like ( like always popping up and asking if I want to save a password ), but I'll figure out how to disable it --- eventually!

Thanks for showing me how to get the old firefox back. This #4 version is a joke!!! If I wanted Bing, I would have downloaded it myself...please don't mess with my preferences!!!!! If this happens again, I will totally delete firefox.

I hated it too ...... Thanks for this link Firefox 3.6

I have used Firefox since it first came out, and always loved it. Firefox 4.0.1 is a different story. This must be one of the worst software upgrades across the board, of any software package I have ever used. I have stuck with it for a few weeks, and I have now finally given up.

Constant crashes, constant freezes, many plugins no longer work, my favorite among them, i.e PDF plugin to see PDF files inside the browser. AppTabs disappear over and over.

I have downgraded back to 3.6.17 and hope things will be better again.