Hello skagrawal, Unfortunately you've picked up some malware, that you will of course want to get rid of. Would you please go to the 3-bar menu => Add-ons => Extensions - if you see anything there that you didn't install yourself : please remove it. Then do the same in Windows Control Panel => All Programs Next step will be to run all malware scans that are listed in this article : https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware (what one doesn't pick up, the other one might) Also see : https://www.pcviruscare.com/blog/remove-http-windowsdefender-club-best-removal-guide 'Hope that helps ......