Sorry you are having problems, but hopefully they may be solvable.

If it is malware you have not yet successfully found and removed two things to bear in mind are that

1. Some malware affects multiple browsers.
2. Malware may continue to damage your computer, data or security.

So just switching browsers may not be much of a solution. My suggestions are as follows

1. Try a clean reinstall of Firefox. That involves removing its program files (NOT the profile files).
2. Then run scans again with multiple and fully up to date tools.
3. If you then get crashes please report what the crash IDs are.
4. Please explain how you get on by posting back to detail what you have tried and what the results were.

Clean Reinstall

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 mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
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.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Thanks

Crash IDs

We're sorry to hear that Firefox is crashing. In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash.

1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste those IDs into the "Post a Reply" box.

Note: If a recent Report ID does not start with bp- click on it to submit the report.

(Please don't take a screenshot of your crashes, just copy and paste the IDs. The below image is just an example of what your Firefox screen should look like.)

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

You can check if you can start Firefox in Safe Mode by holding down the Shift/Options key.

Please post the IDs of one or more recent crash reports that have a "bp-" prefix like posted above.

• bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

You can find the Report ID of recent crash reports on the "Help > Troubleshooting Information" page (about:support).

• Click the "All Crash Reports" button on this page to open the about:crashes page and see all crash reports.

If necessary then you can open about: pages via the location/address bar.

See:

• http://kb.mozillazine.org/Mozilla_Crash_Reporter
• https://support.mozilla.org/kb/Mozilla+Crash+Reporter

Over the last 12 months, I have tried it all. However, as today I could not open firefox, I decided to do a clean re-install for about the tenth time - amazingly, it worked! This scenario has made me angry in the past, as firefox has been my browser of choice for ages. Anyhow, thanks for all your suggestions, but it appears to be working okay now.

Thank you, but as I today revealed to another forum member, having done a clean re-install today, it appears to be working fine now. I have lost track of how many times I have had to completely obliterate it, and then re-install. But for once, it worked! I still can't figure out how it got corrupted, or changed, by things out of my control. My anti-malware programs are always up to date, but they never found anything wrong with firefox. Internet Explorer was okay, but it has now begun crashing, along with windows explorer. I am considering totally stopping use of the internet, and just going back to Windows XP. It has run reliably for me, ever since it was first made available to the public.

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

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

i have marked my own answer as solvingthis thread as you have said twice Firefox is working after you did a clean reinstall.

Your continuing problem is

Internet Explorer was okay, but it has now begun crashing, along with windows explorer.

That is a Windows problem and not something we are ble to help you with here. Have a look for Microsoft's site or some forum dealing with Windows for instance

• http://support.microsoft.com
  • http://support.microsoft.com/solutions/internet-explorer/
  • http://support.microsoft.com/Product/windows/
  • http://support.microsoft.com/gp/microsoft-support-options/
• http://www.pchelpforum.com/windows-xp/