Know more about "This site says... Main Security Error..." pop-up
The "This site says... Main Security Error..." pop-up is caused by an adware or a malware that you may acquire when you download and install third party software. After running into your PC, modifications will be made causing homepage hijacking, unwanted pop-ups and redirection.
In order to draw more attention, "This site says... Main Security Error..." pop-up keeps promoting out as long as you launch the web browser or open a new tab. The message you will see from this malicious pop-up reads:
