How do I tell Internet Explorer to trust a security certificate?

Certificates are supposed to prove that you're connecting to the site you think you're connecting to, something that's particularly important if you're about to share sensitive data with the site or download a program or system patch. I won't even talk about phishing and how that ups the ante of site verification (though you can read about it here: Paypal and eBay alerts: legit or phishing?)

Since having a site certify itself doesn't make sense -- because the site could just as easily have a forged security certificate -- there are third party Certification Authorities that act as what security folk call 'trusted third parties'. It used to be that there were just two or three of these authorities, but now there are more, and what's happened in your situation is that you've somehow ended up indicating to your Web browser, Internet Explorer, that you don't trust the third party certification authority that a particular site is using.

But don't panic. This can be fixed and pretty easily at that. Go into Internet Explorer then choose Tools -> Internet Options, then click on the Content tab. The middle of that window will show you different options regarding Certificates. Click on the middle button, labeled "Certificates..."

Now you'll see something that's an interesting user interface gaffe on Microsoft's

part because the tabs on this window don't fit in the window, so you need to click on the tiny right arrow by the rightmost tab. Once you can see it, click on "Untrusted Publishers". You'll end up with a window that looks like this:

You should see the publisher listed that's causing you such problems. On my screen, I have two certificates from Microsoft, published by VeriSign, as you can see. Just delete the entries here by clicking on each one to select it, then clicking "Remove".

Quit the browser, restart, and everything should be good to go!