Hi, Please also try opening Firefox in a [https://support.mozilla.org/en-US/kb/Managing-profiles new profile]. If you have security software (antivirus, firewall etc.) installed, you can try deleting all existing instances of Firefox and related files in all the different configuration areas/modules of the security software. Instead create new allow/trusted rules for Firefox + its related processes. Even otherwise the security software may also ask again when Firefox is started and you can try to allow/trust at that time. Please see [https://support.mozilla.org/en-US/kb/Firewalls this]. [http://kb.mozillazine.org/Firewalls AV/Firewalls Configuration]