This connection is untrusted in Firefox

This connection is untrusted

This article describes why the This Connection Is Untrusted error message may appear when trying to visit secure (https) websites in Firefox.

For troubleshooting secure connection problems with the error message Secure Connection Failed, see the Secure Connection Failed article.
For troubleshooting other error messages, see Error loading websites.

Certificates and identification

When you visit a website whose web address starts with https, your communication with the site is encrypted to help ensure your privacy. Before starting the encrypted communication, the website will present Firefox with a "certificate" to identify itself.

The certificate helps Firefox determine whether the site you're visiting is actually the site that it claims to be. If there is a problem with the certificate, you will see the This Connection Is Untrusted alert page.

Technical information

Click on Technical Details for more information on why the website's identity information is invalid. Some common errors are described below.
Certificate will not be valid until (date)
(site name) uses an invalid security certificate. The certificate will not be valid until (date). (Error code: sec_error_expired_issuer_certificate)

This error can occur if your computer clock has the wrong date, in which case the date given in the error message will be in the past. To fix the problem, set your system clock to today's date and time (double-click the clock icon on the Windows Taskbar).
The certificate expired on (date)
(site name) uses an invalid security certificate. The certificate expired on (date). (Error code: sec_error_expired_certificate)