NET::ERR_CERT_DATE_INVALID - 7 Ways to Fix it

Encountering the NET::ERR_CERT_DATE_INVALID error can be frustrating, whether you’re just browsing a website or managing one.

This error typically indicates a problem with an SSL certificate’s validity, which can prevent secure connections and trigger browser warnings like “Your connection is not private.”

Since SSL certificates play a critical role in securing data between users and websites, issues with their date settings can cause security alerts.

In this article, we’ll explain what causes the NET::ERR_CERT_DATE_INVALID error and guide you through practical steps to fix it.

What is the NET::ERR_CERT_DATE_INVALID Error?

The NET::ERR_CERT_DATE_INVALID error occurs when there’s a problem with an SSL certificate’s date, such as it being expired, not yet valid, or mismatched with the system’s date settings. This triggers browser warnings like “Your Connection is Not Private”.

SSL certificates are essential for establishing secure HTTPS connections, and they come with a set validity period.

If the certificate is expired, not yet valid, or improperly configured, browsers will block access to the site to protect users from potential security threats.

When this error appears, users typically see a warning message like:
“Your connection is not private. Attackers might be trying to steal your information.”

Screenshot of the ERR_CERT_DATE_INVALID error in Google Chrome.

Why Browsers Show This Error?

SSL/TLS certificates encrypt communication between users and websites. For security reasons, certificates are only valid for a specific timeframe.

If a browser encounters a certificate with an invalid date, it assumes the connection might be insecure and prevents users from accessing the page.

This error can appear in different browsers, but the core issue remains the same—an SSL certificate that fails the date validation check.

What Causes the NET::ERR_CERT_DATE_INVALID Error?

The NET::ERR_CERT_DATE_INVALID error can happen due to various reasons, including incorrect system settings, expired certificates, or misconfigured SSL installations.

Below are the most common causes:

1. Expired SSL Certificate

SSL certificates have a fixed validity period, typically ranging from a few months to two years. If the website owner fails to renew the certificate before it expires, browsers will reject the connection and display this error.

2. Certificate Not Yet Valid

If an SSL certificate has a start date in the future, and a user tries to access the website before that date, the browser will flag it as invalid. This can happen due to:

The issued certificate is not yet active.
The server’s system time is set incorrectly, making the certificate appear invalid.

3. Incorrect System Date and Time

If the user’s device has an incorrect date or time, it may cause browsers to misinterpret a certificate’s validity period, even if the certificate itself is fine.

This is common after battery failures on laptops or when a system clock is manually set incorrectly.

4. Issues with the Certificate Chain

SSL certificates rely on a chain of trust, which includes:

The website’s SSL certificate (end-entity certificate).
Intermediate certificates issued by a Certificate Authority (CA).
A root certificate trusted by operating systems and browsers.

If intermediate certificates are missing, expired, or misconfigured, browsers may fail to verify the certificate’s validity, triggering this error.

5. Outdated Browser or Operating System

Browsers and operating systems maintain a list of trusted root certificate authorities. If a browser or OS is outdated, it may lack the latest root certificates, leading to errors when visiting secure websites.

6. SSL Inspection by Antivirus Software

Some security software, such as antivirus programs and corporate firewalls, intercept and inspect HTTPS traffic. If this process modifies or fails to properly validate certificates, it can cause the browser to flag the certificate as invalid.

Each of these causes directly affects the way browsers validate SSL certificates, leading to the NET::ERR_CERT_DATE_INVALID error. Identifying the specific cause is the key to resolving it effectively.

How to Fix the NET::ERR_CERT_DATE_INVALID Error

1. Inspect the Website’s SSL Certificate

The first step is to verify the website’s SSL certificate. This helps you determine if the issue lies with the certificate itself. Here’s how to check:

Open Developer Tools in your browser (for Google Chrome, go to Settings > More tools > Developer tools)

Screenshot of Google Chrome's settings menu with a highlight on the option for more tools, where you can find the developer tools.

Go to the Security tab
Click on View Certificate

Screenshot of the SSL certificate details window, which you can open from the View Certificate button in the Security tab of Google Chrome's Developer tools.

Inspect the Certificate Details and check the certificate’s expiration date Not before and Not after validity.

If the certificate has expired or is not yet valid, the website owner needs to renew or replace it.

You can also use an online SSL checker to check the SSL certificate’s expiration date and identify any configuration issues.

Snippet of the SSL checker on the website sslshopper.com, with a field for the server hostname and a button to check SSL.

2. Check and Correct System Date and Time

An incorrect system date or time is a common cause of this error. Here’s how to resolve it:

On Windows:
- Right-click the clock in the taskbar and select Adjust date/time.
- Toggle on Set time automatically and ensure the time zone is correct.

Screenshot of Window's time and date settings, with a highlight on the toggle button to set the time automatically.

On macOS:
- Go to System Preferences > Date & Time.
- Check Set date and time automatically.

Screenshot of Date and Time settings on MacOS, with a highlight on the toggle button to set the time zone automatically.

Once corrected, reload the website to see if the issue persists.

3. Update Browser and OS

Outdated browsers may lack the latest trusted root certificates, leading to validation errors. To fix this:

Update your browser to the latest version.
Make sure your operating system is up to date, as root certificate updates are often included in system updates.

If the issue persists on a specific browser, switching to a different one temporarily can help confirm the problem.

4. Clear Browser Cache

Cached certificates or outdated site data can sometimes cause conflicts. Clearing the browser cache can help:

In Chrome, go to Settings > Delete browsing data.
Choose Cached images and files and click Clear data.

Reload the website to test if the error is resolved.

5. Test Without SSL Inspection

Some antivirus programs or firewalls perform SSL inspection, which can interfere with your internet connection and certificate validation. To test:

Temporarily disable SSL inspection in your antivirus or firewall settings.
Restart your browser and try accessing the website again.

If this resolves the issue, consider adding the website to the antivirus’s exclusion list for HTTPS scanning.

6. Clear Your SSL State on Windows

Browsers on Windows rely on the operating system’s SSL cache to speed up secure connections. However, cached SSL data can sometimes cause conflicts, especially after an SSL certificate has been renewed or updated. Clearing the SSL cache forces the browser to fetch the latest certificate information.

To do this:

Open the Control Panel and click on Internet Options.
Switch to the Content tab.
Click Clear SSL State to erase the cached certificates.

Screenshot of the Internet Properties on Windows, where you can clear the SSL state of the device.

After clearing the SSL cache, refresh the website to see if the error is resolved.

On macOS, browsers do not use device SSL cache. To clear outdated certificates on Apple devices, clearing browser cache is sufficient.

7. Check DNS Settings

While the NET::ERR_CERT_DATE_INVALID error is primarily related to SSL certificate issues, incorrect DNS settings can occasionally contribute to connectivity problems that trigger security warnings.

To rule out DNS-related issues:

Flush your DNS cache:
- On Windows: Open Command Prompt and run ipconfig /flushdns.
- On macOS: Open Terminal and enter sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder.
Change your DNS server:
- Go to your network settings and replace your current DNS with the following DNS server addresses – Google’s public DNS (8.8.8.8, 8.8.4.4)

After updating your DNS settings, restart your browser and check if the error persists.

While this won’t fix SSL certificate issues directly, it helps rule out domain name system problems as a contributing factor.

Final Thoughts on Fixing the ERR_CERT_DATE_INVALID Error

The NET::ERR_CERT_DATE_INVALID error is a clear sign that something is wrong with an SSL certificate’s validity or how it’s being verified.

Whether the issue stems from an expired certificate, incorrect system time, outdated browser settings, or even DNS misconfigurations, addressing the root cause is key to restoring secure website access.

For website owners, regular SSL certificate monitoring, timely renewals, and proper server configurations are essential to prevent this error. For website visitors, simple steps like correcting your device’s date and time, clearing cached SSL certificates and updating your browser, can often resolve the error quickly.

While the error may seem alarming, it’s ultimately a protective measure to facilitate secure connections. By following the troubleshooting steps outlined in this guide, you can resolve the NET::ERR_CERT_DATE_INVALID error effectively and maintain a safe browsing experience.