You seem to be on Firefox10 so that will have been a while ago.Why=not try again now.

• Use Firefox Button -> Help -> AboutFirefox [check for updates]
  • If it does not update what message are you getting now ?
    Please paste the message in to your next post. Or attach a screenshot
  • How do I create a screenshot of my problem?

I note from More System Details aside mention of an enterprise edition of McAfee.

• are you on some sort of corporate or educational network ?
  • or using a machine setup or provided by someone else ?

You can also download and install over firefox (downloading with another browser), download from...

• https://www.mozilla.org/en-US/firefox/all/

OR SEE: Update Firefox to the latest release

Try to boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.

You currently have a Firefox 10.0.4 ESR version.

If you prefer to stay on the ESR channel then you can find that version here;

• http://www.mozilla.org/en-US/firefox/organizations/all.html

• http://www.mozilla.org/en-US/firefox/17.0.8/releasenotes/
• http://www.mozilla.org/en-US/firefox/17.0.8/system-requirements/

Yes, it is indeed a corporate provided version. I forgot to mention that. However it never had any issues with applying the updates before and I can't even guess why it suddenly stopped applying updates one day.

Thank you all for the responses.

To "John99": I tried the Help screen, there's no "Check for updates" button because it seems as if the Firefox is stuck on some update what it downloaded but cannot apply. Button is labeled "Apply Update" but pressing that ends up with the same error message. Is there a way to delete that update and force the browser to re-download an update?

To "Waka_Flocka_Flame": I've been thinking about that, I guess the main question is that will such a direct "overwrite" also import the settings and bookmarks?

To "cor-el": I have to admit I haven't yet tried the safe mode option, I will test this as soon as I can. I'll also look about the newer ESR releases, but the question will then be the same as I mentioned to "Waka_Flocka_Flame" - does a direct application of the new version through an installer preserve the data from old browser version, like settings and bookmarks and so on?

Yes it is possible to clear such upgrades

• see this old article Updates reported when running newest version_delete-update-configuration-files

In the end that article did help to clear the "stuck update" but did not help to resolve this update issue. I checked the Users folder:

C:\Users\<name>

And there are folders "Local Settings" and "Application Data". I can't access either of these folders as the Windows tells that the access is denied, even with my user who is the administrator and so on (Windows 7 64-bit, 6.1). There is a folder named "AppData" what I can access:

C:\Users\<name>\AppData\Local\Mozilla\Firefox\Mozilla Firefox

There I was able to find those XML files and the "updates" folder. I deleted all of them and then restarted the Firefox. First change was that the update was gone as I got no message asking to apply the update. I then checked for updates and a 23+ Mb file was downloaded. When download was complete, I clicked on "Apply Update" and the end result was... As the attached pic shows. Same message. Ironic is that I am getting the same error message for Thunderbird as well, though on another PC.

I'll try the safe mode option and if that won't help then plain and direct install of the new version over the old one.

That message is asking you to check if Firefox is still running.

• Did you check that ?
  • Use task Manger. (Ctrl+Alt+Del on earlier Windows now Ctrl+Shift+Esc) look for firefox.exe or plugincontainer in the process tab of Task Manager

Powering down the computer and starting again may be worth a try.

The issue is that this update came through Firefox itself so it doesn't even start up unless I start Firefox. But then I of course have Firefox already running so it seems that the patch cannot apply itself in that case. By the time I get this message it doesn't matter anymore if I kill the process or not because the patch application has already failed, that message is just the "the end" notification telling that "sorry, I tried but no cigar". And I cannot run that "update.exe" or " updater.exe" on it's own, seems like it has to be started through Firefox.

So it's like some vicious circle - I cannot get the updater running without the browser, but I cannot update either if the browser is running.

The updater.exe I think is merely to fix problems with Windows UAC.

What happens if you

1. Close Firefox
2. Clear the failed updates by using the advice from the old kb article
3. Power down the computer.
4. Restart in Windows Safemode with Networking (F8 key on booting)
5. Check to confirm Firefox is not running
6. Check that the deleted files/folders are deleted still.
7. Start Firefox. Firefox should now try to upgrade

If that fails it is a case of trying to upgrade by installing a new version over the top of the existing one. if you try that there should be no need to uninstall the old version but also make sure you do NOT use any option to remove personal information, because that will destroy Bookmarks and passwords.

This was semi-successful though not with Firefox, although it did fix my Thunderbird issue which had the same error message. The safe more with networking option. Though the laptop which has Firefox issue is not yet fully tested, mostly because the safe mode with networking never did start up on it. I guess the wireless isn't something what the safe mode with networking really supports, so I need to get a network cable and try it then. But it's semi-hopeful situation, seeing as Thunderbird issue of same type did get resolved.

That at least is progress and gives you some clues. It is likely to be a problem with something that Windows safemode blocks.

I am no expert on this but I guess the next step would be to run msconfig, and comparing Safemode with ordinary mode look at the Startup and Services tab.

Often firewalls or security software will cause problems with Firefox not starting or not upgrading. Check all your security related software in case that is interfering. It seems odd though that you get a message about Firefox running.

See also

• Configure firewalls so that Firefox can access the Internet
• Fix problems connecting to websites after updating Firefox
• Firefox won't start - find solutions

You could give up on that type of update.

Download the installer for Firefox ESR17

If necessary run the installer in Windows safe mode. The installer from

• http://www.mozilla.org/en-US/firefox/organizations/all.html

appears to be the traditional offline type and not a stub installer.

Take care. There should be no need to uninstall Firefox 10 and do NOT use any option to remove personal settings or you will lose bookmarks and passwords.

Just to finish this off and mark it as completed - the laptop I had the Firefox issue on also has some other issues it seems, one of them being that it doesn't even boot up into Safe Mode. It just get stalled with "Please Wait..." message at some point and that's that.

However, I downloaded the latest ESR version 17 and simply installed it on top of current browser and it worked, no more update issues and browser is also working. So it's resolved, thanks for all the assistance and advice.

Thanks for posting back.
Glad it is resolved and Firefox is working again.

It would have been better to get a current Release of Firefox working. As you now have a working version installed you may actually find you can now install the current Release Firefox 24 over the top of that.