How to Fix ERR_SSL_VERSION_OR_CIPHER_MISMATCH?

[Christian J]

Hello everyone,
I just know that this errors comes may be because of SSL, please help me how can I fix this error.

[Delaney martin]

ERR_SSL_VERSION_OR_CIPHER_MISMATCH occurs when your web browser notices a problem with the SSL certificate version used by the website.


Here we include a step-by-step guide to fix the above error:

1. Check SSL/TLS certificate
So many online tools check the validity of your SSL certificate. Here we use Qualys SSL Labs tool to run an SSL certificate check.



Additionally, it verifies cipher strength, key exchange, and protocol support.




2. Name mismatch in an SSL certificate
The certificate name mismatch occurs when the domain name in the SSL certificate and the URL in the browser doesn't match.

To check the domain name on the certificate of the current site, use Google Chrome DevTools:

1. Anywhere in the browser window, right-click and select Inspect.
2. Choose the Security tab.

3. Now select the View Certificate option to view certificate information.



4. After clicking on the view certificate, a new page will be opened, then select the Details tab.
5. Scroll down and select Subject Alternative Name. Here you see your registered domain name.



3. Old TLS version
The SSL Labs test reveals the TLS version that your website is currently using. Modern browsers no longer support TLS 1.0 and 1.1; therefore, at the very least, it should work with TLS 1.2. The error ERR_SSL_VERSION_OR_CIPHER_MISMATCH may appear if a site still uses an outdated TLS version.




4. Chcek RC4 cipher
The Qualys SSL Labs test also identifies the server's current cipher suite. We advise disabling it and setting up the server to use an alternative cipher suite if it still uses the RC4 cipher suite.




5. Disable QUIC protocol
Google's experimental QUIC (Quick UDP Internet Connection) protocol was created to enhance the User Datagram Protocol (UDP) connection.

Despite being a great substitute for other well-known security solutions like TCP, HTTP/2, and TLS/SSL, QUIC frequently results in the display of warnings like ERR_SSL_VERSION_OR_CHIPER_MISMATCH.

Perform the below steps to disable QUIC:

1. In Google Chrome and type in chrome://flags in the address bar.
2. Search for QUIC in the search bar.
3. Find out the Experimental QUIC Protocol.
4. Select Disable from the dropdown.

6. Clear the cache
ERR_SSL_VERSION_OR_CIPHER_MISMATCH may be resolved by clearing the browser's cache and restarting it.

1. On the right side of the page, click on three dots in your google chrome and choose Settings.
2. Then click on Privacy and Security.
3. On this page, Choose Clear browsing data.

4. A pop-up window opens; check the checkbox with the text Cached images and files option, and then click on clear data.