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Firefox 24 continuously changed back to Firefox 23

  • 4 replies
  • 1 has this problem
  • 3 views
  • Last reply by tommyltk

tommyltk
tommyltk
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I have upgraded and installed from FF23 to FF24 once it was released. Since last week, I encountered problem. One day I started FF24 and it prompted that it had to restart in order to complete previous update of Firefox (however, there was no update triggered by me). I could not start up FF24. Then I restarted my PC. I found that FF23 was installed. Uninstalling and Reinstalling FF24 does not help in this case. I tried to uninstall using normal uninstaller and uninstall manually (deleted all files in program folders and registry). No matter any effect, it somehow and sometimes fallback to FF23. I even have no idea where the FF23 installer was triggered.

Today even worst, when I was using FF24, at around 2pm I found the shortcut bar icon changed to windows setup icon. I closed all firefox and started up again. It prompted the same and I found that it changed back to FF23!

Scanned for virus. No found.

Now I installed FF25b8 to see if the problem persists.

I have upgraded and installed from FF23 to FF24 once it was released. Since last week, I encountered problem. One day I started FF24 and it prompted that it had to restart in order to complete previous update of Firefox (however, there was no update triggered by me). I could not start up FF24. Then I restarted my PC. I found that FF23 was installed. Uninstalling and Reinstalling FF24 does not help in this case. I tried to uninstall using normal uninstaller and uninstall manually (deleted all files in program folders and registry). No matter any effect, it somehow and sometimes fallback to FF23. I even have no idea where the FF23 installer was triggered. Today even worst, when I was using FF24, at around 2pm I found the shortcut bar icon changed to windows setup icon. I closed all firefox and started up again. It prompted the same and I found that it changed back to FF23! Scanned for virus. No found. Now I installed FF25b8 to see if the problem persists.

Chosen solution

Finally it looks I found the problem. It is related to our stupid IT doing something strange.

Thanks for your help

Read this answer in context 👍 0

All Replies (4)

iamjayakumars
iamjayakumars
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Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

tommyltk
tommyltk Question owner
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I also suspected virus or malware. However, quick scan of virus and malware do not find anything.

I have searched through window event log and still no idea what was wrong. Something behind the scene is like a Firefox 23 installer, which can replace everything including files and registry back to Firefox 23. It should not be a simple malware that is capable of.

(
tommyltk
tommyltk Question owner
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Today I started up my PC at around 9:15am. And found it changed to FF23 at around 10am. Below is the log

I have also run a full scan of virus by McAfee but nothing found I installed Microsoft Security Essential as suggested and run a full scan. Also it had nothing found....

Mozilla Firefox Installation Started: 2013-10-18 9:54:11

Installation Details 

 Install Dir: C:\Program Files\Mozilla Firefox
 Locale     : en-US
 App Version: 23.0
 GRE Version: 23.0
 OS Name    : Windows 7
 Target CPU : x86
tommyltk
tommyltk Question owner
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Chosen Solution

Finally it looks I found the problem. It is related to our stupid IT doing something strange.

Thanks for your help