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All of a sudden, after a firefox update, I am getting "This Connection is Untrusted" for Facebook, it doesn't matter if I use http: or https:, WHY????????

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All of a sudden, after a firefox update, I am getting "This Connection is Untrusted" for Facebook, it doesn't matter if I use http: or https:, WHY???????? Here are all the details from the error message:

This Connection is Untrusted

You have asked Firefox to connect securely to 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.

facebook.com uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.

(Error code: sec_error_unknown_issuer)

(Also included a screen shot.)

All of a sudden, after a firefox update, I am getting "This Connection is Untrusted" for Facebook, it doesn't matter if I use http: or https:, WHY???????? Here are all the details from the error message: This Connection is Untrusted You have asked Firefox to connect securely to 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. facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer) (Also included a screen shot.)

Chosen solution

cor-el said

You can check the date and time and time zone in the clock on your computer: (double) click the clock icon on the Windows Taskbar. You can retrieve the certificate and check details like who issued certificates and expiration dates of certificates.
  • Click the link at the bottom of the error page: "I Understand the Risks"
  • Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate"
  • Click the "View" button and inspect the certificate and check who is the issuer.
You can see more details like the intermediate certificates that are used in the Details tab. If you can't inspect the certificate via "I Understand the Risks" then try this: Open this chrome URI by pasting or typing this URI in the location/address bar to open the "Add Security Exception" window and check the certificate:
  • chrome://pippki/content/exceptionDialog.xul
In the location field type/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
Check who is the issuer of the certificate. You can inspect more details like the certificate chain in Details tab of the Certificate Viewer.
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All Replies (1)

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Hi pheczko, it's probably fixable, but we need more information from you.

Which error code are you getting? This may be immediately visible on the page, or it might be in a Technical Details section you need to expand. For example:

  • sec_error_unknown_issuer -- do you run Kaspersky, BitDefender, or ESET?
  • sec_error_bad_signature -- do you run Avast?

Also, have you checked whether Microsoft Family Safety is enabled for you?

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