Start > Run > type: msconfig
Go to the "Start up" tab and disable all programs that are displayed here (with exception of anti-virus)
Reboot PC and it should be solved.
Extra step: Download/install Malwarebytes' Anti-Malware, perform a Threat Scan to see if anything nasty is lurking on your computer.
Delete everything it finds & reboot pc.
I didn't want to disable everything in my start up because most of programs that are in there i want them to be there.
However, I saw "Windows command processor" and when I expand this I saw three files : conhost, mozilla firefox and windows command processor (aka cmd)
I disabled that and voila the problem is solved. I was hoping to delete whatever it was causing it but I only can disable that.
There are web installers out there that have "add-ons" that try to install while you install your program. Most common example is Adobe Flash Player tries to install the online scanner from McAfee while you install Flash....you have to look over these installers closely, some will "hijack" your home page, search engines or install payload that you don't want on your computer....be very careful!