How to Fix "This Connection is Untrusted"

This Connection is Untrusted
You have asked Firefox to connect securely to docs.google.com, but we can't confirm that your connection is secure.
Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.

What Should I Do?
If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

Technical Details
Docs.google.com uses an invalid security certificate.
The certificate will not be valid until 8/11/2011 8:49 PM. The current time is 8/6/2011 12:11 AM.
(Error code: sec_error_expired_certificate)

I Understand the Risks
If you understand what's going on, you can tell Firefox to start trusting this site's identification.
Even if you trust the site, this error could mean that someone is tampering with your connection.
Don't add an exception unless you know there's a good reason why this site doesn't use trusted identification.

Yesterday, when I opened http://send4u.blogspot.com/, I found warning like above. I thought, my internet connection is in trouble. So, I asked my Internet service provider (ISP) about it and he said, there is no trouble with Internet connection. Is there any trouble with my computer system? I asked my self. At the moment, I wanted to reinstall my computer. But before I reinstall my computer, I was looking for Information in Google about it and I found the way to solve it. How to solve it? Look at the bottom right of your computer! Change the date and time setting! The date and time setting of your computer is incorrect. Before you change the date and time setting, restart your computer and do not connect your computer with internet.  I hope, this information is useful for you. Thanks for visiting send4u