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Cant't open a coupe of sites including accounts.firefox.com got http error

  • 1 reply
  • 5 have this problem
  • 2 views
  • Last reply by cor-el

iwaqar
iwaqar
more options

The details are below:

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

This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox Developer Edition only connect to it securely. As a result, it is not possible to add an exception for this certificate."

When I click on advance, I get the following message, "accounts.firefox.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"

A couple of more website are not working like CSS-tricks, got the following error "Your Connection is not secured The owner of css-tricks.com has configured their website improperly. To protect your information from being stolen, Firefox Developer Edition has not connected to this website.

I think I issue is on my site, but i dont know what is the reason for this. and its only happening in firefox dev edition( I am using the latest version) "

The details are below: "The owner of accounts.firefox.com has configured their website improperly. To protect your information from being stolen, Firefox Developer Edition has not connected to this website. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox Developer Edition only connect to it securely. As a result, it is not possible to add an exception for this certificate." When I click on advance, I get the following message, "accounts.firefox.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" A couple of more website are not working like CSS-tricks, got the following error "Your Connection is not secured The owner of css-tricks.com has configured their website improperly. To protect your information from being stolen, Firefox Developer Edition has not connected to this website. I think I issue is on my site, but i dont know what is the reason for this. and its only happening in firefox dev edition( I am using the latest version) "

Chosen solution

If you can't inspect the certificate via Advanced (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 with the https:// protocol prefix (https://xxx.xxx).

  • 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 please attach a screenshot that shows the Certificate Viewer with the issuer.

There is security software like Avast and Kaspersky and BitDefender and ESET that intercepts secure connections and sends their own certificate or that incorporates special web shielding features that can block content.

See also:

If that doesn't help the do a scan for malware.

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All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Chosen Solution

If you can't inspect the certificate via Advanced (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 with the https:// protocol prefix (https://xxx.xxx).

  • 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 please attach a screenshot that shows the Certificate Viewer with the issuer.

There is security software like Avast and Kaspersky and BitDefender and ESET that intercepts secure connections and sends their own certificate or that incorporates special web shielding features that can block content.

See also:

If that doesn't help the do a scan for malware.