Sorry to hear about that. By default, Firefox tries to restore your previous session windows and tabs after a crash, and that might be the problem.

Could you try starting in Firefox's Safe Mode? That temporarily deactivates extensions, hardware acceleration, and some other advanced features of Firefox that might make it more prone to crashing on some systems.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Will Firefox start?

To gain more insight in the crashes, it would be great to see some of your reports. You can share those with forum volunteers by providing the crash report IDs. Please check the support article "Firefox crashes - asking for support" for steps to get those does from the about:crashes page, or if necessary from disk, and then post some of the recent ones here.

Well, more issues...so I tried holding the Shift while starting Firefox and it didn't work, the Crash Reporter box just pops right up. So, I then went to restart Windows in Safe Mode and it gets to a certain point (I don't know the exact executable command), gets stuck on this command and then jumps back to wanting to start in regular mode, not allowing me to get into Safe Mode. Without being able to do either of those 2 options, it doesn't look like I'll be able to use Firefox any longer due basically having an old laptop with old Windows.

The support article about crash reports describes where to find them on disk without Firefox running. Was there anything in that folder?

Without any other leads to go on, two other thoughts:

To rule out possible problems with Firefox program files:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

(1) Download a fresh installer for Firefox 42.0 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(2) Exit out of Firefox (if applicable).

(3) Rename the program folder as follows:

(32-bit Windows folder names)

C:\Program Files\Mozilla Firefox

to

C:\Program Files\OldFirefox

(64-bit Windows folder names)

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

(4) Run the installer you downloaded in #1. It should automatically connect to your existing settings.

Does a cleanly reinstalled Firefox start up normally??

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

• \OldFirefox\Plugins
• \OldFirefox\browser\plugins

To rule out problems with your existing Firefox profile:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST061115, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Any difference?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

Edit: Fixed copy/paste error re: Firefox version.

Thank you for the crash report: https://crash-stats.mozilla.com/report/index/bfb5d373-3c8d-4c3e-92c4-4a1cd2151201

If you click through to the crash report and click the "Modules" tab, you'll see that the first on the list is "FLVSrvLib.dll". That module installs with various Applian Technologies programs including Freecorder and Replay Media Catcher.

This crash is closely associated with having BOTH the Applian software AND Norton security software, or in rare cases Kaspersky security software. Since presumably you don't want to switch away from Kaspersky, you can remove or deactivate the Applian software as follows:

(1) Uninstall & reboot

If you have either of those programs and it isn't essential, try uninstalling it and then restarting Windows to ensure that none of its components are left running.

Will Firefox start normally after that?

(2) Prevent auto-startup

If you prefer not to uninstall the program, a few other users said using the msconfig program to prevent FlvSrvc.exe from running at startup bypassed the problem.

See: http://windows.microsoft.com/en-us/windows/using-system-configuration

You still may need to reboot to unload the software from your current Windows session.

Success?

mcannatella said

Firefox crashed while I had multiple tabs open on Kaspersky site and it locked up, crashed and then popped up with the Crash Reporter and now every time I attempt to open Firefox the Crash Reporter opens. I’ll follow the instructions to report etc., and it’ll then pop up again. I’ll go through the vicious cycle and it’ll pop up again and again and will not let me open Firefox.

jscher2000 said

Thank you for the crash report: https://crash-stats.mozilla.com/report/index/bfb5d373-3c8d-4c3e-92c4-4a1cd2151201 If you click through to the crash report and click the "Modules" tab, you'll see that the first on the list is "FLVSrvLib.dll". That module installs with various Applian Technologies programs including Freecorder and Replay Media Catcher. This crash is closely associated with having BOTH the Applian software AND Norton security software, or in rare cases Kaspersky security software. Since presumably you don't want to switch away from Kaspersky, you can remove or deactivate the Applian software as follows: (1) Uninstall & reboot If you have either of those programs and it isn't essential, try uninstalling it and then restarting Windows to ensure that none of its components are left running. Will Firefox start normally after that? (2) Prevent auto-startup If you prefer not to uninstall the program, a few other users said using the msconfig program to prevent FlvSrvc.exe from running at startup bypassed the problem. See: http://windows.microsoft.com/en-us/windows/using-system-configuration You still may need to reboot to unload the software from your current Windows session. Success?

So first I tried the Clean Install and it didn't work and then moved on to the uninstall of one Applian software, Freecorder, did a Restart on Windows, clicked on the Firefox icon and FINALLY the Crash Reporter didn't pop up; albeit, it did have to bring in Bookmarks from my IE again and all that stuff that comes with installing new, but, thanks to jscher2000 for taking the time with me and getting me back online with Firefox...many thanks jscher2000!