How to Fix ERR_CERT_COMMON_NAME

A brief guide to fix an SSL Common Name Mismatch Error: NET::ERR_CERT_COMMON_NAME_INVALID

Running your website on HTTPS is a standard practice. If you do not install an SSL certificate properly, it may cause an error.

SSL errors can worry users, as numerous errors can interrupt user experience. There are multiple solutions to fix such errors. First, you need to check the cause of such error then; it will not take much time to solve it.

In this short information, we would like to discuss the ERR_CERT_COMMON_NAME_INVALID error, causes, solutions and how it looks in different browsers.

What is the ERR_CERT_COMMON_NAME_INVALID error in Chrome?

ERR_CERT_COMMON_NAME_INVALID, also known as the SSL Common Name Mismatch Error, is one of the SSL errors.

This error is a result of the wrong SSL configuration or browser configuration. It can also be caused by a third-party extension and security programs on a computer, among them antivirus and firewall.

However, this error does not prohibit users from browsing a site but throws a warning that the site may steal private information. The error may appear in the Chrome browser, as shown in the screenshot below.

The browser fails to verify the SSL certificate in this type of error. It may happen due to a mismatch of the domain name, as the actual name displayed in an SSL certificate does not match with the actual domain name.

What is ERR_CERT_COMMON_NAME_INVALID error in Firefox?

Mozilla Firefox displays a different error message than ERR_CERT_COMMON_NAME_INVALID for the same error.

The browser shows “Warning: Potential Security Risk Ahead”. It warns users about potential security threats and says the attackers can steal your information.

The browser does not reveal a particular error code for this error. It warns users not to share private information on the website and offers a solution.

What is ERR_CERT_COMMON_NAME_INVALID error in Microsoft Edge?

NET::ERR_CERT_COMMON_NAME_INVALID error on Microsoft Edge browser shows a different message like “Your connection isn’t private” and warns users that message along with a warning that attackers can steal your information upon accessing a website.

You can either click on Advanced button to further visit a website or click on Go back button.

This error has a few causes, such as antivirus configuration, site address, third-party extension, and firewall setting. So, let us discuss the causes.

Causes of the NET::ERR_CERT_COMMON_NAME_INVALID error

As we stated above that are few causes of ERR_CERT_COMMON_NAME_INVALID error like

Your server has a self-signed certificate that the browser does not recognize it and shows a warning.
Due to ‘misconfiguration HTTPS Redirects’ issue means you have tried to redirect to HTTPS without installing an SSL certificate.
Third-Party Browser Extensions can interfere with an SSL connection and can cause error.
Your proxy system is not properly configured, which can cause error.
Your antivirus is obstructing a secure connection.
Browser cache and SSL State are corrupted.
Your SSL certificate does not work with both www and non-www domains.

However, the main cause is the issued SSL certificate does not pertain to a domain name that the user is accessing in a browser.

Below, we have also given solutions to get rid of this error. So, let us see them individually.

How to Fix ERR_CERT_COMMON_NAME_INVALID error?

Confirm that the correct certificate is installed

The main cause of this error is that the site domain is different from the common name shown in the SSL certificate.

Therefore, it is necessary to fix the SSL certificate configuration. You can find the common name in the browser with a click on a Tune Icon. (Click on Tune Icon >> Connection is Secure >> Certificate is Valid). Alternatively, the SSL checker is also a helpful tool for checking certificate details, including common names.

You can check the below image of certificate details found in the Chrome browser.

The domain name should match the one a user is trying to access. If it does not match, there should be misconfiguration in the SSL certificate.

You should remove the current certificate and install a new one to solve it. In a wildcard SSL, the SSL certificate should cover the subdomain and main domain. In the case of a multi-domain SSL certificate, the SSL certificate should cover the www and non-www versions of a website, subdomains, and different levels of domains.

Check for redirects and Non-WWW vs. WWW

It is not all SSL certificates that cover both non-WWW and WWW domains of the website by default. You should stop redirection to www to Non-WWW or Non-www to WWW depending upon the domain you entered while purchasing the certificate.

It is essential to check with your SSL certificate provider that your SSL should cover the www and non-www domain versions. Therefore, browsers and users will not face any issues while accessing your website.

For example, www.domain.com and domain.com should both be covered by an SSL certificate. The browser will redirect your site to another domain version if it does not cover it. To solve this issue, you can change the common name of a certificate or purchase another SSL certificate to cover another version of your domain name.

WordPress URL is Not Directing to Site URL

If the HTTP protocol is changed to HTTPS manually without installing an SSL certificate, causing “NET: ERR_CERT_COMMON_NAME_INVALID.” Error. If one has WordPress, it is recommended not to put “S” after HTTP if the certificate has not been bought or and installed.

To solve this issue, follow below steps

Open WordPress Dashboard and Click Settings >> General.
Check that WordPress URL and Site Address URL are same or not.
In case both do not match, you should change them.

Check the Browser Extension

The browser extension can be a reason for the ERR_CERT_COMMON_NAME_INVALID error, as too many browser extensions can cause conflicts.

You should access the site in incognito mode to check whether the domain name is accessible. If sites are accessible, then there may be a browser extension issue.

To solve this issue, you should check individual extensions and check the issue. You can disable or delete the extension if needed.

Click on three dots on chrome browser
Now, click on extension and click on Manage Extension
Here, you can disable or delete the extension that is causing this error.

It is necessary to update your extension timely and not add suspicious or malicious extensions if it behaves bizarrely.

Clear the Browser Cache

Browser cache remembers the website address you visited in the past. The reason is that the browser can load websites fast as you visit them in the browser. However, the old cache can cause website access issues, so it is necessary to clear the cache in a browser. Once you clear the cache, the browser will try to load a fresh website version.

Disable Antivirus and Firewall

Antivirus has an HTTPS scanning feature that prevents you from visiting HTTPS sites. If you trust a website, you can turn off the scanning feature. In case of the absence of this feature, you can turn off real-time protection.

Browse Start >> Settings on your PC.
Search Update & Security >> Windows Security
Click Virus & Threat Protection and click Manage Settings.
Here, turn off Real-Time Protection.

Set up URL in phpmyAdmin

If there is a difference in the option value in the site URL and home rows of a website’s database, then ERR_CERT_COMMON_NAME_INVALID can occur. It can be solved with a change in WordPress URL Settings.

You can open the hosting panel, access phpmyAdmin
Select the website’s database
Search for the wp_options
Look for siteurl and home rows.
Make sure both redirects to the same domain name.

Clear the SSL State

SSL common name mismatch error or NET::ERR_CERT_COMMON_NAME_INVALID can be resolved by clearing if SSL cache is there.

To clear the SSL state in Windows, follow the below steps:

Open Control Panel and access Network and Internet >> Internet Options
Click the Content tab in the Internet Properties box and select Clear SSL State.

Update the Browser and OS

Outdated operation systems (OS) and browsers can interfere with SSL connection and cause errors. It is necessary to update the browser version and the OS regularly.

You can update Google Chrome by following the steps.

Click on three dots in the top of the right corner of a browser.
Click Help >> About Google Chrome
Click Update if any is available.

You can also update OS by following the steps.

How to update Windows OS

Go to Settings in Windows
Click on Windows Update
On the right side, click on the Check for updates
If any update is there, it will start updating the windows.

How to update macOS :

Open Apple Menu and choose System Preference
Select Software Update and click Update Now.

Check proxy settings

If your proxy setting is not set to Automatically detect settings, you may face error and affect your browsing experience. This will restrict you to surfing websites on your browser.

To solve it, Go to Internet Options in Windows OS

Here, you need to tap on Connection and click on LAN Settings.

Then, you will have a box where you need to check the box against “Automatically detect settings” and press the OK button.

Now, check whether the error is solved or not. If not, you can try the next point described here.

Check date and time are correct

If the date and time are not properly set on your desktop, then your browser (chrome) will show ERR_CERT_COMMON_NAME_INVALID. You can fix the error by adjusting time and date on your PC.

Self-signed certificate and different domains

When a Self-Signed certificate is attached to a domain name, the browser throws such a warning. However, Self-Signed certificate is used for internal servers. Browsers do not trust Self Signed certificate. In order to solve this issue, you should remove Self Signed certificate and install CA signed SSL certificates, which are trusted by browsers and operating systems.

Conclusion

NET::ERR_CERT_COMMON_NAME_INVALID is a complex error. If you can note the reason for such an error, you can solve it and provide a good user experience.

You should check the browser’s SSL certificate and look for SSL misconfiguration. Follow the above solutions to get rid of NET::ERR_CERT_COMMON_NAME_INVALID.

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How to Fix ERR_CERT_COMMON_NAME_INVALID in Chrome