Hi Stepmom2316, it depends.

If a site's address starts with HTTPS in the address bar, Firefox will attempt to make a secure connection. Are you getting error messages with HTTPS sites? Could you copy/paste the details of the problem? Sometimes the error page will have an Advanced button providing more specific information, so if you see that please click the button to access that section of the page.

If a site's address does NOT start with HTTPS, then your communications with that site are not secured (sent back and forth in plain text, not encrypted). The site might not offer secure connections.

See also:

• https://support.mozilla.org/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

• https://support.mozilla.org/kb/what-does-your-connection-is-not-secure-mean
• https://support.mozilla.org/kb/secure-connection-failed-error-message