Please consider turning on send info to Mozilla before posting a question. This helps us help you. As I have no info from your system that would help see things that cause issues. The crash error is : EXC_BAD_ACCESS / KERN_INVALID_ADDRESS There is not a definitive answer for this one. Especially with no info supplied . You mention you have uninstalled and reinstalled. So will go along with that ask you to please disable all extensions in Firefox. Then please uninstall Firefox and delete all Mozilla Firefox folders in C:\Program Files and C:\Program Files(x86) Then please reinstall Firefox 56.0.2 from a Full Version Installer https://www.mozilla.org/firefox/all/ See how it runs after a reboot. Turn on any Extensions 1 at a time then restart Firefox each time. If Firefox persists in crashing a new Profile may need to be created and see if that works. Note : Firefox 57 Quantum release date Nov 14th https://www.mozilla.org/en-US/firefox/quantum/ Note : Legacy Extensions will be disabled and or removed. Please let us know if this solved your issue or if need further assistance.