A likely cause for this is one of the files that stores details of installed add-ons has become corrupt. You can delete those files and Firefox will re-create them.

First go to your profile folder using the method shown in the profiles article. Then close Firefox and delete extensions.cache, extensions.ini, extensions.rdf, compatibility.ini and if it exists extensions.sqlite. Now re-start Firefox and see if it lets you add or remove extensions.

You are using Firefox 3.6.9.
That version hasn't been officially released yet.
See https://wiki.mozilla.org/Releases/Firefox_3.6.9

Where did you get that version?

Build 1 of 3.6.9-candidate is available in the nightly folder on the ftp server. In addition, it's several places in a Google search:

• rapidshare and megaupload -- who knows what you are really getting there
• a few sites have a link to the nightly ftp folder

I was appalled by firefox crashing continuously because of flash, so i opted for the Beta version which at that time was only firefox download that considered flash as a different process. I see the feature has been added to stable releases now, but everything was working fine so i didn't care to get back to the stable release.

To Helper7677, I guess it would not be right for me to go for nightly builds at this point of time.

Thank you a lot TonyE. It solved my problem. Evrything's working smooth now.

I did this. Deleting extensions...etc... Restarting firefox. Nothing happened. Firefox does not respond at all.

I'm having the same issue -- I cannot install, delete, disable or upgrade any add-ons. The Restart Firefox procedure is not working at all. After a Restart, the Add-Ons section states, "Restart Firefox to complete your changes."

I've tried renaming and deleting the extensions.cache, extensions.ini, extensions.rdf, compatibility.ini and extensions.sqlite files, and Firefox recreates those files when I log back in with the same issue present. I've also checked Task Manager to make sure Firefox is completely shut down, which it would have to be to rename or delete the above extentions. Starting Firefox in Safe Mode also doesn't solve the problem.

Short of creating a whole new Profile, which would be a major pain, I'm at a loss as to what to try next. I'm currently using Firefox 3.6.10, which I downloaded with the use of the "Check for Updates" button, and I'm running Win XP.

As at least 20 other people are having the same issue, I hope that someone can find a solution sometime soon.

Thanks.

BTW, this thread is labeled as "Solved". While it may have helped at least one person, there are a few of us that have tried all the suggestions above and are still having the same issue.

Any further suggestions would be appreciated.

This is for those of you who tried the suggestions above and still have add-on issues.

Eureka! I have found the culprit! After using MR Tech Toolkit to disable all of my add-ons, Java Console showed a large red ! next to it, stating it was incompatible with Firefox 3.6.10. This red exclamation point was NOT showing up before. I slowly re-enabled each add-on and retested for functionality until Java was the only add-on not enabled. With Java disabled, I was able to uninstall the Console, then went to Java's site and downloaded the most recent version, jre-6u21-windows-i586-s.

Java is back and my add-ons now work. Hope this helps someone else.

I have same problem as "Smarty7", and his 29 others, and also as "Colleto18" and THIS THREAD IS NOT SOLVED! I followed the solutions they were given, deleted the requisite files & did everything else, Firefox is still non-functional in the restart mode: nothing uninstalls, nothing installs, nothing can be enabled or disabled, nothing can be updated or added. The restart appears to happen, then when FF comes back up, the Restart message is still there and nothing has changed, nothing has happened and so on and on we go, it seems now into infinity. Why is this so hard and why do the solutions suggested not work, do not make any difference? Everything stays the same, with the same malfunction, no matter what I do. HELP!!! Note also to "Tarquin", good for you if finding your Java situation took care of this error for you - it does not for me. I checked out everything Java related as you recounted, but mine is all OK, all applications are up to date & current with the proper, latest Java update and all Java stuff is functioning and properly enabled, so as much as I wish it were the same for me, I still have the same issue with FF Restart function. Again, SOMEBODY HELP PLEASE! (Again, also, I am running Windows XP with Service Pak 3).

Hi to Colleto18: I did the same thing you did, deleted all the files they suggested etc and nothing happened. All the files I deleted just keep on recreating themselves (I checked, as I tried to fix this several times, it just keeps on deleting, recreating and still nothing changes in regards to the original problem with Restarting FF and etc). I don't know what to do - I can't uninstall any add-ons or install any new ones, I cannot disable any add-ons or enable any, I cannot install any updates that become available for the add-ons I want to keep that are still compatible with FF 3.6.10, nor can I disable/uninstall any add-ons that are not compatible or any that I just decided that I would like to get rid of. My FF browser has become, just in the past week, for no apparent reason, completely non-functional in this aspect and I am beyond frustrated. It is one thing if you report a problem & someone posts a solution that actually works - but in this situation, the solutions do not work and I am not savy enough to know what to do next, except maybe to get rid of FF completely and switch back to IE (perish the thought! Yuck!) or perhaps I'll consider switching to Google Chrome, after I uninstall everything Firefox (if that will even work anymore). If I sound cynical, it is because I have had FF for almost 2 years now and have been a huge fan, but it seems to be getting worse instead of more stable. I have more problems as time goes by, not less. I no longer can use the bookmark function and I cannot access my bookmarks, and my history does not function or save the way it is supposed to. This problem cropped up a few months ago, when FF was crashing like crazy on me - I had one really bad crash and afterwards, KaBoom!!! No more bookmark function, no more bookmarks, history is capricious (sometimes some of it is there & sometimes, more often than not, it is just "gone", kapoot!) I found many other people in support articles with the same problem and so I followed those solutions and surprise, surprise - none of them worked. So I have just been "living without" my bookmarks and my history, and not very happily either. The only thing I did not do was the whole ordeal of creating a new profile. Also, if I choose View, Sidebar, Bookmarks and enter lower case "aaa" into the bookmark search box, BINGO, there are my bookmarks. This is the only way they come up, so they are floating around somewhere within my FF cyberspace, where I do not know. If I just try to View Bookmarks, they won't come up - ever since this happened, when I try to bring them up the proper way, I get this same, weird little list of about 4 or 5 bookmarks that I NEVER MADE! Don't know where these came from or why they are floating around in my system. And the bookmark function never works, ever, cannot ever make a new bookmark anymore. And the history is just gone, gone, gone - I have not found any odd little tricks to make it re-appear like the bookmarks. So I have decided just to live with this huge inconvenience - at least until this new issue with the impotent Restart function began last week. Now I am fit to be tied. With the bookmarks & history, I did not delete all my places.squiltes files (I know that is spelled wrong, sorry!) because they say this will wipe out all history and bookmarks that may exist, and all browsing history and I did not want to do that. Before I will do that, I will use my little "bookmark trick", detailed above, and spend the hours it will take to sit in front of the computer screen and manually, long-hand, make a list on notebook paper of all my bookmarks, before they might be lost forever, so that I have a record, a list of all those websites that I wanted to remember. Frustrated In Corona, California.

I think the solution which worked well for me, isn't working for many other people. Can i make the post again open for answers? undo my selection of solution?

My suggestion would be to backup bookmarks(profiles, if any). do a clean uninstall, remove every firefox folder(commonFiles, Application data, everywhere) from computer then do a clean install. This problem is not a bug, so should be solved by that for sure.

@georgiepeach i see you are frustrated but it is a forum, try to be brief to let people read and solve your problem. :) BTW how do i make this post 'unsolved'?

Have you tried this: http://support.mozilla.com/en-US/kb/The+program+must+close+to+allow+a+previous+installation+attempt+to+complete

My issue is not like others. It started when I installed 4.0 b7. I, still, have 3.6.12, my default, and 3.5.16 pre. All accessed with different profile, using the -p switch. 4.0 b7 started by not heeding my command to not start (until I entered the profilename), and it made itself default, no questions asked. After that, whenever I clicked on a mail, or web link, my default program opened with the 4.0 b7 profile. If I use the shortcut, everything is cool. But, if 3.6.12 opens, even for a msec, with the 4.0 b7 profile, when I go back, and try to open 4.0 b7, using the shortcut two or more extention are missing. And, I can install them over and over again. They are there now, and gone pretty soon. I am trying a new profile, and if the problem persists, goodbye 4.0 b7.

If you are like me, and are mainly concerned about your bookmarks and recovering addon functionality, you can try making a new profile. These details apply to Ubuntu Linux, however Windows (yuck) versions have similar functions but you will have to look for details. First backup your bookmarks. Click the bookmarks link and select "Organize Bookmarks". Select "Import and Backup", then "Backup". Save it to a location you will remember. If you have a version of Firefox without this function you can backup the file manually in your profile folder. It is located (default location) in (username)/.mozilla/firefox/(random#'s).default/ and the file to backup is named "places.sqlite". You will need to select "View" and check the "Show hidden files" box to navigate to it. Next, determine if a new profile will fix the issue. Press "alt + f2" to open a run window. Then type "firefox --profilemanager" without quotes and click run. Select "Create Profile" and follow the prompts to create a new one. Then be sure the new profile is highlighted and click "Start Firefox". You should notice all of your old settings and bookmarks missing and the default setup of Firefox. Attempt to install an addon and check its functionality. If this works then your profile is corrupt and you need to use this new one. Now let's grab our bookmarks so we're not starting from scratch. If your firefox version contains the "Organize Bookmarks" link under Bookmarks, select it. Go to "Import and Backup" select "Restore" and "Choose File" then choose the file that you saved previously. That should do it! You can delete the old profile that is broken and use only the new working one. For those without this function manually navigate to the new profile and replace the new profiles "places.sqlite" with the copy that you backed up from your old profile. Hope this helps some of you. Note: Windows users can do this as well but the specifics will be different. Good Luck!

I am using Mac OSX and this solution "First go to your profile folder using the method shown in the Profiles article. Then close Firefox and delete extensions.cache, extensions.ini, extensions.rdf, compatibility.ini and if it exists extensions.sqlite. " works for me.

this is all well and good, but I downloaded 4.0 from the firefox site. It downloaded, then said I had to restart. I restarted and it always says I must restart. I tried to uninstall it but it says I must restart for the prior download first. In other words it will let me do nothing. Now firefox won't work at all. Any suggestions for this.

Just tell me how to uninstall this garbage

@jsandels:
Run the Firefox program once as Administrator (right-click: Run as Administrator).

If that doesn't help then do a clean reinstall.

• Download a fresh Firefox copy and save the file to the desktop.
• http://www.mozilla.com/en-US/firefox/all-rc.html
• http://www.mozilla.com/en-US/firefox/all.html
• Uninstall your current Firefox version and remove the Firefox program folder before installing that copy of the Firefox installer.
• Don't remove personal data if you uninstall the current version.
• It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

You do not need to create a new profile, that is not necessary for this issue

Your bookmarks and other profile data are stored elsewhere (not in the Firefox program folder) and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.

• http://kb.mozillazine.org/Uninstalling_Firefox

Where the heck is people from firefox to help us resolve issues? That is what I want to know !!!!!!