Problem with Security Alert popping up

Something is wrong with my computer. Everytime I bring up a web page in my Internet Explorer, my computer pops up a Security Alert, telling me "The security certificate has expired or is not valid.... Do you want to proceed?" I click "yes" and I'm good to go.

This pops up on my favorite and trusted sites I've been visiting for years. I went through the motions of installing the certificates as requested, but the message still pops up, irregardless.

This is not normal. How can I fix this?

Dell Dimension 4700
Windows XP

 

Is your computer's clock right?

Next time you see the warning, click to view the certificate. Look for the beginning and ending date/time for when the certificate is valid, and compare it to the time your computer thinks it is. If the computer is wrong, fix it. If the cert is really outside its valid time range, it's their problem. You can complain, but otherwise can't do anything about it.

In theory, when you see any message about a certificate not being valid, you should not trust the site to be what you think it is. However, it really isn't very likely that someone got an old cert and is trying to spoof the site, so I would go ahead.

 

Doh!

I set the clock back so I could use some software (a CD manual for my car) that won't work otherwise. Naturally, I forgot to set it back to present.

Thanks for nailing this.