How To Fix Error Code: NET::ERR_CERT_DATE_INVALID

When it comes to transmitting any private information it’s vital to recognize the warning signs your browser displays. Especially when there is a problem with the security of the website you are visiting. Since SSL certificates are issued for a predetermined amount of time, one of the most basic problems that can occur with any security certificate is as simple as the certificate reaching its expiration date. That said, an expired certificate error also doesn’t necessarily mean the certificate is expired.

Today we dive into the process of troubleshooting these types of invalid or expired errors in our journey to How To Fix Error Code: NET::ERR_CERT_DATE_INVALID.

How to recognize expired SSL certificates?

Before we can cover the potential causes associated with How To Fix Error Code: NET::ERR_CERT_DATE_INVALID, we must first be able to recognize the error as it appears our browsers. It may seem trivial at first, but all browsers are not created equal. In fact some browsers very purposefully behave differently than others, ahem, I’m looking at you Microsoft. Kidding aside, it’s not just a bad habit of Microsoft, but many browser developers.

But why is that? I’m afraid it’s the nature of the beast. Browser developers work hard on making their brand of browser to be unique so that it stands apart from the crowd, and man these days, this crowd is expansive. So that leaves us in a bit of a bind when it comes to identifying error messages in the different variations of browsers so widely available in the modern world.

How To Identify Expired Certificate Errors In Your Browser

Recognizing expired certificate errors can differ between each browser variant family. You might say that a big line of delineation between browser families is the specific set of error codes and message verbiage used by each. So trying to identify a specific error code may not be as straight forward as one might think when crossing the lines between these families. Sometimes the entire error message is changed, making it troublesome to decipher if the error message you saw in Firefox is the same one thrown by Chrome variants (it isn’t). Take a look at the following simplified matrix of Expired Certificate Errors by Browser based on using the Chrome error code NET::ERR_CERT_DATE_INVALID, you can see how the error message changes between each family:

Chrome, Firefox, and Edge (IE Mode only) use fundamentally different error codes. This is mainly due to the history of their unique predecessors. Opera and Microsoft Edge are technically Chrome variants, but they have diverged enough from the originals they have become their own family. Apple Safari focuses on straight forward error messages, instead of complicated technical jargon that might otherwise confuse their target audience. The above messages are all mostly equivalent, though the less specific approach by Apple can make it difficult to know what part of an SSL certificate chain is faulty. Nevertheless we can troubleshoot the generic Apple message the same way we would deal with other related certificate errors.

In our example above we can see the error message can changed significantly between browser families. However, lets take a look into what these error messages look like in the wild, directly in each of these browser engines as there is no substitute for the real thing.

What is Error Code: NET::ERR_CERT_DATE_INVALID?

In its simplest interpretation, this error code means the certificate has expired or more accurately, the certificate is outside of its defined validity period. The validity period is expressed by both a certificate’s start and end dates. These two dates define the range of time that this certificate will pass validation checks by the certificate authority that issued it. Expired certificates are by far the most common cause of NET::ERR_CERT_DATE_INVALID and when genuinely expired, are very straight forward to fix.

How to fix invalid certificate date errors?

Instinctually, the answer here is to replace or renew the expired certificate, and that is the correct answer when this error occurs naturally. However, like many things in the technology world of today, the solution is not always the obvious one that we intuit.

What if I told you that it’s entirely possible, that the expired certificate error you are receiving is not an issue with the expiration date or the certificate at all? Kind of misleading, eh? Lets consider what happens when your browser does its customary expiration checks for the certificate.

In order for a browser to pass a certificate’s expiration check we must look at a number of additional factors beyond the obvious. Review the following list that outlines a typical browser certificate date validation check:

As you can see, its entirely plausible for an SSL certificate to have an accurate expiration date, yet still be seen as expired by the visitor’s browser. The date/time settings on both the visitors device and the server must also be set correctly. Otherwise, the browser has the wrong point of reference for validating the date range checks. So now we can see how important having the correct date, time, & time-zone settings on our devices is, as it’s a prerequisite for SSL certificate validation to work correctly.

Take a look at our companion guide to troubleshooting SSL certificate errors.