Enable SSL to fix the Firefox cannot connect securely error message

This article is no longer maintained, so its content might be out of date.

Starting in Firefox 34, Secure Sockets Layer version 3.0 (SSLv3) is blocked by default because it is no longer secure (for details, see this blog post).
Warning! Your version of Firefox uses Secure Sockets Layer 3.0 (SSLv3) which is no longer safe (for details, see this blog post). To stay safe online and protect your information you should update Firefox to the latest version.

Websites that use the Secure Sockets Layer protocol (SSL) such as banking sites and online stores will have "https" at the start of their address. If Firefox can't access a secure site, it will show an error page saying:

An error occurred during a connection to (site name). Can't connect securely because the SSL protocol has been disabled. (Error code: ssl_error_ssl_disabled)

This article will describe how to enable SSL in Firefox if you get this message.

Check your SSL settings

  1. In the Menu bar at the top of the screen, click Firefox and then select Preferences or Settings, depending on your macOS version.Click the menu button Fx89menuButton and select Settings.
  2. Select the Advanced panel.
  3. Click the Encryption tab.
  4. Verify that Use SSL 3.0 and Use TLS 1.0 are check marked.
    • If both boxes are check marked, this section does not apply. You can skip to the next section.
    • If both Use SSL 3.0 and Use TLS 1.0 are not check marked, check mark both of them.
  5. Close the Settings page. Any changes you've made will automatically be saved.
  1. Type about:config in the address bar and press EnterReturn.
    A warning page may appear. Click Accept the Risk and Continue to go to the about:config page.
  2. Type security.enable in the Search field.
    • If both security.enable_ssl3 and security.enable_tls are set to true, skip to the next section.
    • If both security.enable_ssl3 and security.enable_tls are set to false, double-click each of them to set it to true.

Try to access a secure site again. If it still doesn't work, continue in the next section.

Check your proxy settings

Some computers are configured to access the Internet through a proxy.

  1. In the Menu bar at the top of the screen, click Firefox and then select Preferences or Settings, depending on your macOS version.Click the menu button Fx89menuButton and select Settings.
  2. Select the Advanced panel.
  3. Click the Network tab.
  4. Click Settings….
    • If Manual proxy configuration: is selected, you are using a manually configured proxy server. Verify that all protocols listed in the dialog box are pointing to the address of your proxy server. Contact your network administrator if you don't know this address.
    • If Manual proxy configuration: is not selected, this section does not apply. You can skip to the next section.
  5. Make any changes, and click OK to close the Connection Settings window.
  6. Close the Settings page. Any changes you've made will automatically be saved.

Try to access a secure site again. If it still doesn't work, continue in the next section.

Security software

To use SSL protocol, Firefox needs to make a connection to itself. Some security software can block this connection. For information on how to configure security software to allow Firefox the access it needs, see Configure firewalls so that Firefox can access the Internet.

Problem with a specific site

You can test your browser for SSL functionality. If your browser passes the test, the problem may be specific to the site you're trying to access.




Based on information from SSL is disabled (mozillaZine KB)

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