How to Fix ERR_SSL_VERSION_OR_CIPHER_MISMATCH Error in Windows

The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error appears when your browser cannot establish a secure connection with a website. It usually means there is a mismatch between the SSL/TLS settings supported by your browser and those used by the website.

This guide explains what causes the ERR_SSL_VERSION_OR_CIPHER_MISMATCH error and how to fix it on Windows 10 and Windows 11.

What Causes ERR_SSL_VERSION_OR_CIPHER_MISMATCH

This error typically occurs due to outdated security protocols or misconfigured SSL settings.

Common causes include:

• The website using outdated SSL or TLS versions
• Unsupported cipher suites
• Old or unpatched web browsers
• Incorrect system date and time
• Antivirus or firewall interference

In most cases, the issue is not caused by your internet connection.

Check If the Problem Is Website-Specific

Before making changes, confirm whether the issue is local.

Try the following:

• Open the website on a different browser
• Check the site on another device
• Use an online SSL checker tool

If the site fails everywhere, the issue is likely on the website’s server.

Update Your Web Browser

Outdated browsers may not support modern SSL or TLS standards.

Make sure:

• Google Chrome, Microsoft Edge, or Firefox is fully updated
• You restart the browser after updating

Updating often resolves SSL compatibility issues immediately.

Enable TLS 1.2 and TLS 1.3 in Internet Options

Windows manages SSL and TLS settings centrally.

Steps:

1. Press Windows + R
2. Type inetcpl.cpl and press Enter
3. Go to the Advanced tab
4. Scroll to the Security section
5. Check Use TLS 1.2 and Use TLS 1.3
6. Click Apply and OK

Restart your browser after making these changes.

Clear Browser Cache and SSL State

Old cache or SSL data can trigger errors.

You can:

• Clear browser cache and cookies
• Clear SSL state from Internet Options

This forces the browser to establish a fresh secure connection.

Reset Network Settings

Network misconfigurations can also cause SSL errors.

You can try:

• Resetting network settings
• Flushing the DNS cache
• Restarting your router

These steps help clear outdated network configurations.

Final Thoughts

The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error is usually caused by outdated security protocols or browser compatibility issues. In most cases, updating your browser, enabling modern TLS versions, or correcting system time resolves the problem.

If the error appears only on a specific website, the issue is likely on the server side and must be fixed by the site owner.

FAQs

What does ERR_SSL_VERSION_OR_CIPHER_MISMATCH mean
It means the browser and website cannot agree on a secure encryption method.

Is ERR_SSL_VERSION_OR_CIPHER_MISMATCH dangerous
No, it is a security warning that prevents unsafe connections.

Can this error occur on Windows 10 and Windows 11
Yes, it can appear on both versions.

Does clearing browser cache fix this error
Sometimes, especially if cached SSL data is outdated.

Can antivirus software cause this error
Yes, some antivirus programs interfere with SSL connections.