Hello,

Try Firefox Safe Mode to see if the problem goes away. Safe Mode is a troubleshooting mode, which disables most add-ons.

• You can open Firefox 4.0+ in Safe Mode by holding the Shift key when you open the Firefox desktop or Start menu shortcut.

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article for that.

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help other users who have the same problem.

Thank you.

I do still have the Firefox button on my desktop. I tried holding the Shift key and clicking it as you suggested, and nothing happens. No safe mode box opens. What else can I try?

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

I have done that now as well. The icons come back on my desktop after installation, but when I click on them nothing happens. Ugh, so frustrating. I have been using firefox for Years, and am so comfortable using it I feel lost right now. (sounds lame, but true)

Hello wendypter, try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) and check firefox again.

(If works in Windows Safe mode then you have a problem with other software, like security software or maybe a system driver, that is running on your computer).

thank you

That did work! Do you have any suggestions on how/where I start to look for the solution for that?

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 Safety Scanner
• MalwareBytes' Anti-Malware
• TDSSKiller - AntiRootkit Utility
• Hitman Pro
• ESET Online Scanner

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!

Hello wendypter, first disable completely your security software (antivirus, firewall, antispyware) and see if firefox works correct, if yes, then you must find the problematic software, enable one at a time and check it.

second(if the above does not solve the issue) you must update your system driver !

probably the problem is in security software.

thanks again

Problem Solved! My Firefox now opens.

I have had the same issues and tried everything that is suggested here. I could only open Firefox when my computer was started in safe mode.

I managed to get Firefox running again after running ‘Spybot – Search & Destroy’ on my PC. It found a lot of things which I removed. However, I couldn't remove one program 'Babylon Toolbar' without right clicking on the Spybot desktop icon and selecting 'run as administrator'. I restarted my PC, it scanned and then I clicked on 'search and destroy' to remove the software. Straight away Firefox reopened.

I also used MozBackup to back up both my Firefox and Thunderbird profiles and settings etc.

I hope that is of help as I know how frustrating it is and I much prefer to use Firefox than other browsers. I was very close to switching to Chrome!