« Automatically hide file extensions in Windows | Finally! Drag and drop to reorder Windows taskbar buttons »

May 5, 2006

Firefox "Software Update Failed" problem: solved!

I'm a big fan of the Mozilla Firefox browser. And as of version 1.5, it will automatically download and install new updates as they are released. This is great and all, except that I've had a problem with the last two security updates (v1.5.0.2 and…

After it downloads an updated version, you must restart Firefox to complete the installation. When Firefox restarts, I see a message informing me that it's installing the newer version. But then I would receive the following error message:

Software Update Failed
One or more files could not be updated. Please make sure all other applications are closed and that you have permission to modify files, and then restart Firefox to try again.

I could restart the computer and the error message would still appear the next time I tried to launch Firefox. The only solution I was able to come up with was to manually download and install the new version from Mozilla's web site. I was beginning to think that the auto-update feature was broken or just too buggy to use. Until by chance I happened to discover the cause of my troubles… Y'z Dock. Y'z Dock is a freeware program that adds a Mac OS X-like dock to Windows. It's a great way to launch frequently used programs and I have an icon on my dock to start Firefox. Apparently, because this program monitors each program that has an icon on the dock (so that it can change the program's icon to indicate if the program is currently running) this was interfering with the Firefox update. All I had to do was temporarily close Y'z Dock and the installation was able to complete without any further errors!


If my solution does not resolve your problem, Mozilla has a couple of support resources with additional solutions to try:

Posted at 8:21 AM in Computers


1. Randy says:

OMG, all this time i thought the Firefox updater was broke! Geeze.. i didnt think anybody else still used Yzdock!
who would'a thought?


Posted on June 1, 2006 at 8:18 PM

2. Josh says:

Thanks so much for this fix... I have had the same problem the past 2 security updates, and when i recieved my new one today, it worked just fine with my dock disabled!

Posted on June 3, 2006 at 2:53 PM

3. Tater says:

Thank you so much! This was the fix I was looking for.

Posted on October 2, 2006 at 12:07 PM

4. Chris says:

You may have just saved me a big headache. Thanks!

Posted on December 21, 2006 at 6:17 PM

5. Orinoco says:

Well, you're no help to me. I got the same problem but i never even heard of YzrDock or whatever its called. So help me too. , i think its AVG but im not sewer. Ta ta.

Posted on December 23, 2006 at 7:53 AM

6. Bryan Campbell says:

Wow...Thank you SO much. I was getting ready to snap my laptop in half i was so ticked off. That really helped out...THANKS!!!

Posted on December 23, 2006 at 11:20 AM

7. James says:


That problem has been bugging me for sooooo long! Same problem with the Y'z dock! Crazy but thanks so much for posting!!


Posted on December 25, 2006 at 2:36 AM

8. Ivan says:

thank you very much!

Posted on December 28, 2006 at 4:35 AM

9. Jovon says:

ok, so i gave up on firefox for about two months because i couldn't figure this out. got it now. Thanks!!!

Posted on January 5, 2007 at 9:22 AM

10. gianluca says:

Great. Thank you very much!
How Can you find this solution?

Posted on January 29, 2007 at 2:20 PM

11. vprince says:

I had the same problem, and it turns out Mozilla thunderbird, of all things, was the cause. Closing Thunderbird fixed the issue for me.

Posted on February 24, 2007 at 8:01 AM

12. Calin says:

OMG... thank you so much for the solution... it finally fix the problem

Posted on February 24, 2007 at 7:37 PM

13. IcyT says:

Thank you very much! I couldn't find it out by myself. After reading it, I was laughing because I thought it's a bug in Firefox. Sorry Firefox for blaming you ;)

Posted on February 26, 2007 at 12:04 PM

14. rsv says:

YOU KICK BUTT! I thought I was doomed. I was ready to go IE again!

Posted on February 26, 2007 at 2:20 PM

15. Drew says:

Must be more YZ Dock users out there than I thought,

I've fought this for months.

Closed YZ Dock and the UPdate went without a hitch.

Back to the Startup folder and YZ is back without Rebooting.

Awesome Help Thanks

Posted on March 23, 2007 at 11:51 PM

16. RC says:

This problem also happens with the "Aqua dock" (same functionality and some people says is a reshacked version of Y'z).
Anyway the problem with the update get's solved as well just by closing the Aqua dock down while the update is finished.


Posted on February 11, 2008 at 1:31 AM

17. MD says:

On Vista this happens when you try to start Firefox from a shortcut. You need to use Start | Programs | Mozilla | FireFox

Posted on October 18, 2008 at 4:14 AM

18. Richard Davies says:


Start | Programs | Mozilla | Firefox is also a shortcut... so I doubt that makes any difference.

Posted on October 18, 2008 at 10:01 AM

19. MD says:

Actually I am correct. I have now tried and tested this on 2 machines with the same issue and it worked on both.

And you're actually wrong with your statement. Start Programs starts it in "C:\Program Files\Mozilla Firefox" whereas a desktop shortcut loads it from some environment vars. Compare the properties of each 'shortcut' and you will see what I mean.

Posted on November 2, 2008 at 12:37 PM

20. MD says:

I take it your lack of response means you agree with me?

Posted on November 4, 2008 at 3:16 PM

21. Richard Davies says:

MD, I take it your eagerness to make sure you're right and I'm wrong means that you're an immature, pimple-faced nerd with no friends and the social skills to prove it.

Actually, my lack of response is due to an inability to verify your statements. My Vista machine doesn't have a Firefox "shortcut" on the desktop.

Posted on November 5, 2008 at 6:57 AM

22. MD says:

No Richard, or should I call you Dick? I'm an IT Consultant and have never had pimples. It seems that anyone who comes up with the actual simple answer must be some twat with pimples who sits on his own in the corner of his bedroom. The next time Mozilla release an update (I had one today) use the method I suggested and if it still fails let me know otherwise stop offending people who actually bother to contribute to your site.

Posted on November 14, 2008 at 2:01 PM

23. KPM says:

MD it didn't work for me. I've tried shutting down all the processes that Vista will allow me too, but I still get the message.

Posted on November 14, 2008 at 2:20 PM

24. Richard Davies says:

"No Richard, or should I call you Dick?"

Ooooh, I feel very insulted now... reminds me of when I was in 5th grade. I guess my character assumption wasn't that far off...

Ok, IT Consultant, let me teach you something. You said, "On Vista this happens when you try to start Firefox from a shortcut. You need to use Start | Programs | Mozilla | FireFox"

As I said earlier, Start | Programs | Mozilla | Firefox IS a shortcut. So don't try telling me that I'm wrong because you failed to distinguish between a regular shortcut and some sort of specialized shortcut that you've got on your desktop.

As I said, I doubt using your suggestion of the start menu shortcut will make any difference, because that's the way I normally launch it.

Posted on November 14, 2008 at 2:22 PM

25. MD says:

Lets remind ourselves who started the insults. I'll take the advice you use on your glider pic at the top of the page and 'rise above' your derogatory comments. Try this the next time you see the 'updates warning'. Browse to C:\Program Files\Mozilla Firefox\ and launch the firefox.exe from there. It's the same as the Start | Programs solution. I know it works and if anyone else actually uses this site (which I doubt based on your attitude) then hopefully someone will confirm this.

Posted on November 14, 2008 at 2:46 PM

26. Richard Davies says:

That was one of the first things I tried when I experienced this issue. If that was all it took to resolve the problem, there would have been no need for me to write this blog post.

And if my solution wasn't helpful to anyone, then no one would have left comments on this post to say thanks. (You doubt that anyone uses this site, so I guess you didn't bother to read any of the 16 comments prior to yours.)

And it looks like you didn't read KPM's comment in which he confirms my suspicion that your solution doesn't work.

Posted on November 14, 2008 at 2:56 PM

27. DokeBoy says:

Hey, this does work. Richard, MD is right. I also got an update today and used his approach and it worked, Way to go MD! Woohoo!

Posted on November 14, 2008 at 2:59 PM

28. MD says:

OMG - thank you DokeBoy. Richard, actually I got fed up reading the suggestions in the previous comments because they were the same as I read in all the other forums...convoluted approaches to a simple solution. If you actually re-read KPM's comments he states "I've tried shutting down all the processes that Vista will allow me too, but I still get the message". Who told him that? Not me! This must be the standard of people who use your site - except for DokeBoy - he's da man! - and me of course ;-)

Posted on November 14, 2008 at 3:06 PM

29. Richard Davies says:

Wow, both MD and DokeBoy commented from the exact same IP address! http://tinyurl.com/5wdru8 Imagine that.

Yes, please re-read KPM's comment---the whole comment. After stating your solution didn't work, he states "I've tried shutting down all the processes that Vista will allow me too". Note that he used "too" (as in "also" or "in addition to") and not "to". So he's saying he tried your solution and he *also* tried shutting down processes, but that didn't work either.

Thanks for the comments. It's been fun. But I'm done with you... and your "buddy" DokeBoy.

Posted on November 14, 2008 at 3:19 PM

30. AM:PM says:

In the red corner we have Richard, in the blue corner we have MD (aka Dokeboy) lol. Guys take a break! If it helps at all, Richard when I first got this error I used your approach and it works 100%. I had another update today (like MD aka DB) and I tried his/her approach (no insult meant - I don't think you have said if you were mail or female?) and it worked. So:
1. Richard, take it easy. I agree slightly with MD - you were very quick to insult him.
2. MD, if you post a forum post don't demand an answer. There is no SLA here ;-)

Now..both say sorry!

Posted on November 14, 2008 at 3:48 PM

31. Scott says:

Just launch it in safe mode, its seemed to fix the problem for me.

Posted on November 15, 2008 at 8:11 PM

32. el Ridiculoso says:

Just wanted to chime in here and say thanks for the lead on this. For me it was my Blackberry Desktop Manager that was doing me in. I turned that off temporarily, and blammo, Firefox did its thing.

Posted on December 19, 2008 at 10:53 PM

33. Liam Carson says:

Ok, first off, stop arguing over nothing MD and Richard Davies. The idea of this article is to help people solve the problem, not to bitch at each other and waste time and space. MD, I think you are wrong, however if you can supply EVIDENCE for it working I would be interested to see if you are correct.

In regards to the actual problem, I followed all steps and it made no difference, and also AVG Anti-Virus didn't cause any of the problem/s. I uninstalled Firefox and then re-installed from here;

http://www.mozilla-europe.org/en/firefox/ (UK&EUROPE)

and have not had any problems since. If none of the ways suggested by others work for you, do what I did, (Uninstalling and Re-installing of Firefox) and don't worry: uninstalling Firefox will NOT remove any of your Bookmarks, Saved Passwords etc, ONLY if you leave the Remove Personal Data box unticked in the Uninstallation wizard.

Liam Carson.

Posted on December 21, 2008 at 6:42 AM

34. Pablo says:

Frankly, the thing that bothers me is that Firefox continues to attempt a reload after each error so you get into an infinite loop of errors with Firefox constantly running. Add on top that the update process will not work with other instances of Firefox running.
Even shutting down the process from theTask Bar spawned a reload.
Loved Firefox but any software that gets itself into infinite loops that the user needs to reboot out of is a problem.

Posted on January 7, 2009 at 9:59 AM

35. Susan says:

I have had this problem on Vista for weeks and finally Googled it today to try and fix it (landed here). I have never heard of Yzwhatever, so I tried MD's suggestion first since it seemed easiest. (Programs->Mozilla Firefox folder->Firefox (there was plain firefox and firefox safe, I picked the plain one). I have no idea if this was a shortcut or not, but this worked for me.

Once it came up, the first thing it said to do was download the latest version, so I wound up doing that too. So, perhaps downloading the latest version is the least you can get away with (assuming its not just a simple yzwhatever or blackberry thing). Anyway, pleased to know several things to try the next time it comes up--thanks to everyone.

Posted on February 20, 2009 at 11:13 AM

36. Christian says:

Awesome! Thank you for saving my sanity. This happens with Aqua Dock as well.

Posted on March 9, 2009 at 6:48 AM

37. Buddy says:

This didn't work for me, but what did was running Firefox as an administrator. Updated correctly first time I tried it!

Posted on March 13, 2009 at 9:00 PM

38. Brennan says:

Thanks so much, Richard! I love Firefox but that update feature was killing me! I've had to uninstall and reinstall Firefox and I really didn't want to have to do it again. I Googled the bug and found this. I use Aqua Dock, which is just like Y'z Dock and acts like Mac's docking program. I turned it off and tried to update Firefox and SUCCESS! Terrific!! Thanks again!

Posted on March 29, 2009 at 11:00 AM

39. Jaymee says:

Hi, I dont know what Yzdock is, and idk if i have it on my computer or not. But the software update wont stop appearing and trying to instal itself, & I cannot close it. How am I suppose to re-downlad firefox if the error hasn't gone away?! Help? Thanks

Posted on April 24, 2009 at 3:25 PM

40. Richard Davies says:

Jaymee, use Internet Explorer or another browser to manually download Firefox.

Posted on April 25, 2009 at 3:26 PM

41. chris says:

hahah, thanks a lot! i've had this problem for months now and finally a solution! much love, chris

Posted on April 28, 2009 at 12:13 AM

42. doug says:

i have had this problem for a long time. pausing protection on kaspersky solved it for me.

Posted on August 11, 2009 at 9:00 AM