How do I disable the warning Chrome gives if a security certificate is not trusted?

When you use Chrome's Options > Manage Certificates > Import where are you placing the certificate? On the "Certificate Store" screen of the import, choose "Place all certificates in the following store" and browse for "Trusted Root Certification Authorities." Restart Chrome.

You can avoid the message for trusted sites by installing the certificate.

This can be done by clicking on the warning icon in the address bar, then click

"Certificate Information" -> Details Tab -> Copy to file

Save the certificate, then double click on the certificate file. On the certificate window that opens, click install certificate, then walk through the install.

The next time you go to the site it should work fine without errors.

For Chrome on OSX, here's a relatively easy way to add the self-signed certificate to the system's Keychain, which is used by Chrome: Google Chrome, Mac OS X and Self-Signed SSL Certificates. No more annoying red warning screen! (I do wish Chromium would simplify adding the exception though.)

Instructions for Linux (Chrome 12+):

Certificate Information -> Details -> Export

Save the certificate as a file of your choice.

Preferences -> Under the hood -> Manage certificates -> Authorities

Import the file and check all the boxes when it asks. You are done.

It is very important to import under the Authorities tab, and not other!