Computer problem, can't access mai

For some reason this computer decided it doesn't want to access yahoo mail or any other email service, upon further investigation I've found that it won't access anything that usually prompts you that you are going to an insecure location.

I've tried every bit of troubleshooting I know and I can't figure out what the problem is.

Any suggestions?

explorer or firefox?

try checking internet settings, i think yahoo mail needs cookies enabled

Explorer.

well that's your first problem