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How to add security certificate

  • 6 tontu
  • 29 am na jafe-jafe bii
  • 1 view
  • i mujjee tontu mooy stevech

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I'm using the latest (21.05.16) ver of Firefox - 46.0.1 and when I wanted to open youtube.com I was presented with blank webpage saying "The owner of www.youtube.com has configured their web site improperly. To protect your information from being stolen, Firefox has not connected to this web site.

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." Now in the past, when I knew that the site is secure, whenever I saw info like this I just went to "advanced" and added the site certificate as an exeption. But now all I can see is "www.youtube.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" and no button to add the site certificate as an exeption. I just did Firefox Refresh as I had problems with my IP detection so maybe this has something to do with vanishing this option/button. How can I bring it back?

I'm using the latest (21.05.16) ver of Firefox - 46.0.1 and when I wanted to open youtube.com I was presented with blank webpage saying "The owner of www.youtube.com has configured their web site improperly. To protect your information from being stolen, Firefox has not connected to this web site. 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." Now in the past, when I knew that the site is secure, whenever I saw info like this I just went to "advanced" and added the site certificate as an exeption. But now all I can see is "www.youtube.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" and no button to add the site certificate as an exeption. I just did Firefox Refresh as I had problems with my IP detection so maybe this has something to do with vanishing this option/button. How can I bring it back?

All Replies (6)

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hi binks, when such an error appears on major sites like youtube it means that something on your system is meddling witch secure connections - so you should address the root cause of that (instead of adding en exception). could you give us more information about the error by clicking on the error code, copying the text to the clipboard (like shown in the screenshot) and then pasting it here into a reply in the forum.

thank you!

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Now I'm afraid it's impossible. I've closed Firefox, thinking that it'll close all the processes and when I open it again it'll load any missing components, hoping that it might help, and it did. Now whenever I'm opening youtube or some preferences in google I don't see any issues. Why is that? Why just closing browser and opening it again solved my problem?

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maybe your security software is at play here intercepting secure connections and it has injected its certificates into firefox again after a restart - How to troubleshoot security error codes on secure websites

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This happened to me after I uninstalled and reinstalled Firefox in a futile effort to stop Ajax requests from timing out while debugging local webapps using Netbeans.

I find it ironic that even this page's (yes, the one we're on right now) CSS got blocked, so it's almost impossible to work with - it turns out that in a modern UI, unstyled content just isn't all that usable. See error message below from tabzilla-min.css:

"mozorg.cdn.mozilla.net 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 can't even get to secure Google sites at all; the "Add Exception" button basically shows me a refusal and a bunch of binary content.

I doubt that some other software is intercepting requests because this only happens in Firefox (so I now rely heavily on Chrome, which I would rather not do), and only happened after my regrettable decision to reinstall Firefox.

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@stevech, are you a user of eset security software? if yes -> https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER#w_eset

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Yes, it did! Thanks for the tip.