Best ways to Solve “SEC_ERROR_EXPIRED_CERTIFICATE” Error in Mozilla Firefox and Google Chrome

The “SEC_ERROR_EXPIRED_CERTIFICATE” error occurs when a website’s SSL certificate has expired, causing browsers like Mozilla Firefox and Google Chrome to flag the site as insecure. This error prevents users from accessing websites with outdated or expired SSL certificates, as modern browsers prioritize security and encrypt user data over secure connections.

When you encounter this error, it indicates that the SSL certificate associated with the website you are trying to visit is no longer valid. If you’re a website owner or a user encountering this error, this guide will walk you through the best ways to fix the SEC_ERROR_EXPIRED_CERTIFICATE error in both Mozilla Firefox and Google Chrome.

What Causes the “SEC_ERROR_EXPIRED_CERTIFICATE” Error?

The error is triggered when a website’s SSL certificate reaches its expiration date. SSL certificates are issued for a fixed time period (typically 1 to 2 years). After the certificate expires, the browser will not recognize it as a secure certificate, causing the SEC_ERROR_EXPIRED_CERTIFICATE error.

Other possible causes for the error include:

1. Expired SSL Certificate on the Website: The website’s owner has not renewed or updated their SSL certificate.
2. Incorrect System Date and Time: An incorrect system date can cause SSL certificates to appear expired, even if they are still valid.
3. Cache and Cookies Issues: Cached SSL information may be causing the browser to mistakenly flag the certificate as expired.
4. Outdated Browser: An outdated version of the browser may not properly validate new certificate formats.
5. Improper Server Configuration: Missing intermediate certificates or incorrect SSL chain configuration on the server can cause issues.

How to Fix “SEC_ERROR_EXPIRED_CERTIFICATE” in Mozilla Firefox

Here are some of the methods to resolve this error in Mozilla Firefox:

1. Check and Update the Date and Time on Your Device

An incorrect system date can cause SSL certificates to appear expired or not valid, leading to the SEC_ERROR_EXPIRED_CERTIFICATE error. Ensure that the system date and time are accurate.

Steps to Adjust Date and Time on Windows:

1. Right-click the time in the bottom-right corner of your screen and select Adjust date/time.
2. Toggle Set time automatically on.
3. If the time is still incorrect, click Change to manually adjust the date and time.

Steps to Adjust Date and Time on macOS:

1. Click on the Apple logo in the top-left corner of the screen and choose System Preferences.
2. Select Date & Time and ensure Set date and time automatically is checked.
3. If the time is still incorrect, adjust it manually.

After adjusting your system’s date and time, restart Firefox and check if the error is resolved.

2. Clear Browser Cache and Cookies

Sometimes, cached SSL data or outdated cookies can cause SSL validation issues. Clearing Firefox’s cache and cookies can help resolve the issue.

How to Clear Cache and Cookies in Firefox:

1. Click on the three horizontal lines (hamburger menu) in the top-right corner of Firefox.
2. Go to Settings > Privacy & Security.
3. Scroll to Cookies and Site Data and click Clear Data.
4. Select Cookies and Site Data and Cached Web Content, then click Clear.

Once this is done, restart Firefox and check if the issue persists.

3. Manually Add the SSL Certificate as Trusted

If you’re encountering the SEC_ERROR_EXPIRED_CERTIFICATE error on a specific website and trust the site, you can manually add the certificate to Firefox’s list of trusted authorities.

How to Add a Certificate Manually in Firefox:

1. Click on the lock icon next to the URL bar of the site you are visiting.
2. Click More Information and then View Certificate.
3. Click Export to download the certificate.
4. Go to Firefox settings > Privacy & Security > View Certificates.
5. Under the Authorities tab, click Import, and select the downloaded certificate.
6. Check Trust this CA to identify websites and click OK.

Restart Firefox and check if the error is resolved.

4. Disable SSL Scanning in Antivirus Software

Sometimes antivirus software with SSL scanning enabled can cause SSL certificate errors. Temporarily disabling SSL scanning may help fix the issue.

How to Disable SSL Scanning in Antivirus:

• Open your antivirus software.
• Look for settings related to SSL scanning or web protection.
• Disable SSL scanning temporarily and check if the error is resolved.

Once you’re finished troubleshooting, remember to re-enable the SSL scanning feature for added security.

5. Update Firefox to the Latest Version

Outdated browsers may not properly handle SSL certificates, leading to errors like SEC_ERROR_EXPIRED_CERTIFICATE. Ensure that your Firefox browser is up-to-date.

How to Update Firefox:

1. Click the three horizontal lines (hamburger menu) in the top-right corner.
2. Select Help > About Firefox.
3. Firefox will automatically check for updates and install them.
4. Restart Firefox and try accessing the website again.

How to Fix “SEC_ERROR_EXPIRED_CERTIFICATE” in Google Chrome

If you’re using Google Chrome and encountering the SEC_ERROR_EXPIRED_CERTIFICATE error, here’s how to fix it:

1. Check and Correct the Date and Time

Ensure your computer’s date and time are set correctly, as an incorrect system clock can cause SSL certificate validation failures.

Refer to the section above for instructions on how to update the date and time in Windows and macOS.

2. Clear Browser Cache and Cookies

Just like in Firefox, clearing the cache and cookies in Chrome can help resolve certificate errors by removing outdated data.

How to Clear Cache and Cookies in Google Chrome:

1. Click the three vertical dots (menu) in the top-right corner of Chrome.
2. Go to Settings > Privacy and Security > Clear browsing data.
3. In the Basic tab, select Cookies and other site data and Cached images and files.
4. Click Clear Data.

Once done, restart Chrome and visit the site again to see if the issue persists.

3. Update Chrome to the Latest Version

Older versions of Chrome may not support the latest SSL/TLS protocols, causing certificate errors. To fix this, ensure you are using the latest version of Chrome.

How to Update Google Chrome:

1. Click on the three vertical dots (menu) in the top-right corner.
2. Go to Help > About Google Chrome.
3. Chrome will automatically check for updates and install them if available.
4. Restart Chrome after the update.

4. Disable QUIC Protocol in Chrome

In some cases, the QUIC protocol (Quick UDP Internet Connections) can interfere with SSL/TLS connections. Disabling it can help resolve certificate errors.

How to Disable QUIC Protocol in Chrome:

1. Type chrome://flags in the Chrome address bar and press Enter.
2. Search for QUIC in the search bar.
3. In the Experimental QUIC protocol section, select Disabled.
4. Restart Chrome and check if the error is fixed.

5. Manually Add the SSL Certificate to Chrome (for Trusted Sites)

For advanced users who trust a specific website’s SSL certificate, you can manually add the certificate to Chrome’s trusted authorities.

How to Add a Certificate in Google Chrome:

1. Visit the website that throws the error.
2. Click on the lock icon in the address bar and then click Certificate.
3. In the Certificate Viewer, click Export and save the certificate to your computer.
4. Open Chrome Settings, search for Manage certificates.
5. In the Authorities tab, click Import and select the saved certificate.
6. Choose Trust this CA to identify websites, and click OK.

Conclusion

The SEC_ERROR_EXPIRED_CERTIFICATE error is a common issue that can prevent users from accessing websites with expired SSL certificates. Whether you are a website owner or just a user encountering this error, you can follow the methods above to resolve the issue in Mozilla Firefox and Google Chrome.

For website owners, it’s important to regularly monitor and renew SSL certificates before they expire to avoid such errors for your visitors. Users can fix the error by adjusting system time, clearing cache, updating browsers, and adding certificates as trusted if necessary.