When I open forouzan.com.au on firefox, a window pop up said: security connection failed, www.forouzan.com:433 uses an invalid security certificate.the certificate is not trusted because it is self-signed But I am typing forouzan.com.au, not forouzan.com, it is two different websites. This website works fine on other browsers. I believe this is not a Firefox personal setting issue, because everyone who use Firefox to open this website got the same problem, and works fine on other browsers. You can try it from your computer. The weird thing is when I try to open a website, and Firefox told me security connection failed to another website. Can any one tell me why this happened?