SSL Error – Certificate Not Trusted

When you access a website through a secure connection, it is a common issue to get a warning (SSL error) that the certificate is not issued by a trusted authority.

The exact warning message you will get depending on your browser is:

  • Firefox 3 - "The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)"
  • Internet Explorer 7 - "The security certificate presented by this website was not issued by a trusted certificate authority."
  • Google Chrome - "The site's security certificate is not trusted!"
  • Safari - "Authentication failed because the server certificate is not trusted."

If you get one of the above warnings, this means that your browser does not trust the SSL certificate because it is not signed by a company that the browser recognizes as trusted.

The two most common reasons for this warning are:

* The website is using a self-signed/free SSL certificate.
* The website is using a private SSL certificate but it is missing a CA (Certificate Authority) certificate.

The solution in the first case is to purchase a private SSL certificate which is issued for the specific domain by a trusted authority.

The solution in the second case is to have the SSL certificate reinstalled with the correct CA bundle. The CA bundle is provided by the SSL vendor and should be included in the private SSL package.

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  1. Reply August 21, 2015 / 13:23 Roderick KennedySiteGround Team

    Siteground's certificate is invalid. Chrome error on login:

    Your connection is not private

    Attackers might be trying to steal your information from (for example, passwords, messages or credit cards). NET::ERR_CERT_DATE_INVALID

    • Reply August 24, 2015 / 07:31 Ivan StefanovSiteGround Team

      There was a slight issue with the WildCard SSL certificate for *, which we managed to resolve in Saturday. If you however still experiencing any kind of issues with the SSL of your server, please open a ticket in your Help Desk and my colleagues from the support team will help you further.

    • Reply February 10, 2016 / 16:20 KimberlySiteGround Team

      I'm having that same error! Ugh!

      • Reply February 11, 2016 / 15:58 Ivan YordanovSiteGround Team

        We would be happy to assist you with that - please open a support ticket describing the issue and our support team will fix it as soon as possible.

  2. Reply August 25, 2015 / 16:01 ABRSiteGround Team

    I get the invalid cert error when I try to connect to an Exchange Server, apparently hosted by you, from my iOS device. For now, my solution is to not connect...

    • Reply August 26, 2015 / 15:25 Ivan StefanovSiteGround Team

      You should verify the exact Secure SSL settings for your mail account from your cPanel -> Email Accounts -> More -> choose Configure Email Client from the drop down menu. If you experience any further issues with the connection to an Exchange Server, please submit a support ticket from your User area and we will be glad to assist you!

  3. Reply September 30, 2015 / 18:34 bobSiteGround Team

    some of my clients are getting this error when they visit the site Same as Roderick:

    Siteground's certificate is invalid. Chrome error on login:
    Your connection is not private
    Attackers might be trying to steal your information from (for example, passwords, messages or credit cards). NET::ERR_CERT_DATE_INVALID

    I put in a support ticket and was told everything is okay. this needs to be addressed. I can't have clients not believing in my ability because the site warns them that I cannot be trusted

    • Reply October 2, 2015 / 07:37 Ivan StefanovSiteGround Team

      Bob, I carefully checked the SSL certificate of your server and your ticket (1403217), which was submitted more than a month ago, and confirmed that the issue has already been fully resolved.

      You could verify that the certificate is fully trusted by visiting this link.

  4. Reply March 25, 2016 / 23:20 SteveSiteGround Team

    When I try to login to the SiteGround cPanel X via Firefox I get the following message.

    "The owner of has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website."

    • Reply March 28, 2016 / 07:04 Ivan StefanovSiteGround Team

      Steve, the issue is most probably caused by the hostname that you are opening through HTTPS. On our shared servers we're using a wildcard SSL certificate for * and that is why when you open you are redirected to The SSL certificate for your server is configured properly and you may verify it from here.

      However, if the hostname that you are accessing through HTTPS is, and not - the self-singed certificate warning will show up as is explained in this article.

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