According to your user agent string you are currently using Firefox 3.6.15.

If you are posting this from a different computer, to go back to Firefox 3.6.15 you can uninstall Firefox 4, but do not select the option to "Remove my Firefox personal data". You can then install Firefox 3.6.15 available from http://www.mozilla.com

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

What problems are you having with Firefox 4?

thanks for responding.... yes, F/4 is on another computer. It was difficult to browse ... Some sites were slower to load or got hung up. There were also some (virus scan) tools that were not compatible with F/4.

Follow this link , it is related to your problem: http://facebook25.blogspot.com/2011/04/how-to-remove-latest-firefox-update.html

Official Old Version Release http://www.mozilla.com/en-US/firefox/all-older.html

While you can always downgrade by uninstalling the current version uninstalling the current version and reinstalling an old version from http://www.mozilla.com/en-US/firefox/all-older.html it would be better if we could find out specifically what problems you are having and try to fix those.

If Firefox is crashing for you after the update see Troubleshoot Firefox crashes (closing or quitting unexpectedly) for help, if there's another problem, please give details and we'll try to assist you.

Dont Listen To The Corporate Pressure Rhetoric

Official Old Version Release http://www.mozilla.com/en-US/firefox/all-older.html

new version is the worst Firefox ever, no lip.

Upgrading won't get any easier in the future. Fx5 is looming. I suggest you go back to Tony E's question "What problems are you having?"

Tell us about your setup. How many tabs do you use? How many Extensions? Have you checked Problematic Extensions? Do you have Third Party Toolbars? Are your plug-ins such as Flash up to date. Do you have any unusual plug-ins?

I know I'm going back to Square One but have you tried Firefox Safe Mode and creating a new clean Profile.

To find a solution a clear picture of the problem is necessary. Simple appearance problems - re buttons lost or mis-placed, Menu Bar missing and so on - can be solved in the Search Firefox Help box above.

I'm backing out V4 primarily because it's tying up my machine running XP. Acts as if there's a memory leak - gradually gets slower, not due to cpu usage but the disk is working flat out. There are a number of other gripes that I could learn to live with - first time in this position using Firefox - but the 'killer app' or is it 'dis-app? - is performance.

I agree with you. I don't use my computer much but the games that I do play if there is any motion in them they are so slow it drives me nuts and I give up playing. Have wondered about uninstalling and then re-installing the old version, and now that I know that you can I am going to do just that.....

Firefox 4 has many issues. The main one that I have is that not one of the plugins that I rely upon work with this newest version. I also lost all of my bookmarks and went through three weeks of trying to recover them without any success. I will never upgrade automatically again and have been using ie for most of my online work now, due to these issues. I always save my bookmarks to ie now rather than trust Firefox. I lost a lot of valuable references that took me months to locate and they just went swoooosh, gone. But, like I said the plugins are what really left me more than annoyed. I know that the plugin developers are the ones that need to update but still I use these and need them for my work online. So it is back to an earlier version for me too.

Raief, strongly suggest you start a new thread detailing the particular plug-ins. Also with wider details of your set-up. You're a bit lost here.

Your problems don't sound like those caused by the usual plug-ins such as Flash, Java etc.

Just to be sure we are talking about the same thing -

Add-ons = Extensions + Themes(Skins) + Plug-ins.

All is right in the Firefox world again - I uninstalled V4 and re-installed 3.6.17 under XP, deleting V4 and re-installing using the link provided above. I also nailed the files suggested by TonyE.

Whoopee! 3.16.7 rocks! V4 leaves a bitter aftertaste however but I blame myself somewhat for breaking a cardinal rule - never instal version x.0 of anything unless you require stress and agro in your life or are a blooming masochist!

Firefox 4 is probably the most un-successful "new" Product since the "New Coke Formula" and the Ford Edsel!

It has been a DISASTER for me and many I know.

The cgi order form button on my own website does not work for anyone using Firefox 4.

Darn annoying and folks take ages ordering, press the button, assume it has gone though, and sadly nothing reaches me. Annoyed clients and large loss of money for me.

Tonight I tried to book a complicated multi city International itinerary on United Airlines site. Spent 30 minutes getting it right, went right to "Purchase" page and the SAME issue ..... click "BUY" button - and ZILCH.

Removed Firefox 4, did it all again, and worked fine using Firefox 3.6.

Thanks Firefox for wasting a good hour of my time tonight.

Tech boards all over the globe have reported these glitches for quite a while on order buttons, and the geeks there seem to be all asleep.

Bill Gates must be laughing his head off - and you now have Microsoft's VISTA on your hands.

They did not fix that either, and folks still use it as an example of an "UPDATE" that should never have been released as the bugs were never Beta Tested out.

Glen

I received an automatic update for FF 6.0.1 yesterday & since this update I can't get into my game Zooworld that I play every day. When I tried to go to my game it told me I needed the updated version of Adobe Flash Player yet when I tried to download it, it stopped downloading at 55% & said this was already in use. I want to go back to the Mozilla FF version that was in place before the update to 6.0.1. Please help me I want to play my game. BTW, I don't know what version of FF I had before this update. I think it started with a 3.

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