Many have reported issues using the 64bit Firefox. Install the 32bit version from; Download Firefox For All languages And Systems {web link}

If there is still a problem, you may need to downgrade.

Having spent the last couple of days experimenting with these crashes, I come with some interim results. Switching to 32 bit didn't help, and downgrading to earlier versions didn't solve the problem either. Which brought me to the conclusion that Firefox was not the only cause and appearance of the problem merely coincided with Quantum upgrade. Since I have very few programs set to auto update, KAV (Kaspersky internet security) became the primary suspect and disabling it has removed the problem. I am now going to enable debug logs in Windows and reproduce the crash. I will send the full memory dump to Kaspersky, but I would also like to send it to Mozilla, because obviously both programs are involved in the problem. Is there any way I can use this board to forward this kind of information?

duracotus said

Switching to 32 bit didn't help, and downgrading to earlier versions didn't solve the problem either.

Here's what I find odd if downgrading shouldn't have caused the same problem would indicate a O/S issue has occurred is more likely. BSOD is more common with corrupt Windows sys files that is affecting FF launches. What you need to do is complete uninstall any FF version and then Offline download FF and install again to verify it isn't a FF but a Windows problem.

WestEnd said

Here's what I find odd if downgrading shouldn't have caused the same problem would indicate a O/S issue has occurred is more likely. BSOD is more common with corrupt Windows sys files that is affecting FF launches. What you need to do is complete uninstall any FF version and then Offline download FF and install again to verify it isn't a FF but a Windows problem.

Well I have turned Kaspersky off yesterday morning and not a single crash happened since then, doesn't it mean that it was the cause rather than Windows? And again, problem was always linked to actions performed in FF, other programs didn't trigger it. The interesting thing is that I've bought Kaspersky in the first place because similar incompatibility of FF with Avast occured approximately a year ago.

Also, I did not try to install FF from the scratch because I am afraid of losing my bookmarks (which I have plenty of).

duracotus said

I did not try to install FF from the scratch because I am afraid of losing my bookmarks (which I have plenty of).

Firefox comes in two or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user folders would not be affected.

Hello again. After two days of unsuccessful attempts to reproduce the crash in order to create the dump file, I have concluded that it no longer occures. I do not know whether the last KAV program update did it (there was one last week), or the suggested FF reinstall from the scratch (I also did that, and I actually believe this to be the more likely cause of problem's disappearance). In any case, my FF no longer crashes. Thank you all for your help.

As long as the problem is gone. Safe surfing.