What problem you are getting with that ? Untrusted Connection might be . This is because of no valid certificate found when firefox trying to redirect into a website and your antivirus doesn't found the certificate to communicate with that. If This is the problem then follow these steps :

• Go to open Menu > options
• Under Advance tab click on certificates
• Now Import the certificates from your windows program drive,basically it was under C:\ProgramData\Kaspersky Lab\AVP15.0.1\Data\Cert\ (fake)Kaspersky Anti-Virus Personal Root Certificate.cer with marking trust websites only .

note : for doing that click on" show hidden files" from system's "File and Folder options" .

Unlike some other security vendors, Kaspersky does not plan its update schedule for its Firefox add-ons to coincide with the browser's official release. There is always a delay before Kaspersky's browser add-ons will work with a new version of Firefox.

If you can't live without those add-ons, then you could consider using a version of Firefox that updates less often, the "Extended Support Release" version of Firefox 31. More info: http://www.mozilla.org/firefox/organizations/

i just uninstall it a got a bowser that well work with it

not firefox r google crap