This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Èròjà atẹ̀lélànà yii ni a ti fi pamọ́ fọ́jọ́ pípẹ́. Jọ̀wọ́ béèrè ìbéèrè titun bí o bá nílò ìrànwọ́.

www.facebook.com uses an invalid security certificate

  • 5 àwọn èsì
  • 51 ní àwọn ìṣòro yìí
  • 7 views
  • Èsì tí ó kẹ́hìn lọ́wọ́ krmc

more options

All other websites seem to work fine, but when I try to visit Facebook, I get an error message as follows:

This Connection is Untrusted You have asked Firefox to connect securely to www.facebook.com, but we can't confirm that your connection is secure. Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified. What Should I Do? If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox only connect to it securely. As a result, it is not possible to add an exception for this certificate. www.facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. (Error code: sec_error_unknown_issuer)

I have tried following many of the suggestions on these forums, but to no avail. when I looked up the certificate it says its from OpenDNS, Inc

All other websites seem to work fine, but when I try to visit Facebook, I get an error message as follows: This Connection is Untrusted You have asked Firefox to connect securely to www.facebook.com, but we can't confirm that your connection is secure. Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified. What Should I Do? If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox only connect to it securely. As a result, it is not possible to add an exception for this certificate. www.facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. (Error code: sec_error_unknown_issuer) I have tried following many of the suggestions on these forums, but to no avail. when I looked up the certificate it says its from OpenDNS, Inc

Ọ̀nà àbáyọ tí a yàn

Thanks for your response. I spent quite a while going through the websites and trying various changes, before giving up. And this evening I discovered that the internet I was using had blocked Facebook, so it looks like it is not a problem with my computer. But again thanks for your help.

Ka ìdáhùn ni ìṣètò kíkà 👍 9

All Replies (5)

more options

There is security software like Avast and Kaspersky and BitDefender and ESET that intercept secure connections and send their own certificate.

http://www.ehow.com/how_11385212_troubleshoot-reset-connection-firefox.html

https://support.mozilla.org/en-US/kb/server-not-found-connection-problem

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

http://kb.mozillazine.org/Error_loading_websites

This Connection is Untrusted is sometimes caused because the computer system clock is wrong. Check the time / date / time zone settings.


Separate Issue; Your System Details shows;

Installed Plug-ins

Adobe PDF Plug-In For Firefox and Netscape 10.1.16 Adobe PDF Plug-In For Firefox and Netscape 15.9.20069
Having more than one version of a program may cause issues. You must remove the older programs. Then get the current full installer.

Adobe PDF Plug-In For Firefox and Netscape: Adobe Reader Version 2015.009.20069 Note: McAfee Security is offered in the download.

more options

Ọ̀nà àbáyọ Tí a Yàn

Thanks for your response. I spent quite a while going through the websites and trying various changes, before giving up. And this evening I discovered that the internet I was using had blocked Facebook, so it looks like it is not a problem with my computer. But again thanks for your help.

more options

If you can't inspect the certificate via "I Understand the Risks" then try this:

Open the "Add Security Exception" window by pasting this chrome URL in the Firefox location/address bar and check the certificate:

  • chrome://pippki/content/exceptionDialog.xul

In the location field of this window type or paste the URL of the website.

  • retrieve the certificate via the "Get certificate" button
  • click the "View..." button to inspect the certificate in the Certificate Viewer

You can inspect details like the issuer and the certificate chain in the Details tab of the Certificate Viewer. Check who is the issuer of the certificate. If necessary then you can attach a screenshot that shows the certificate viewer.

more options

That was very good work. Well Done. Please flag your last post as Solved Problem so others will know.

Did your provider say why they blocked Facebook?

more options

It seems to just be personal preferences