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"This connection is untrusted error" on Firefox Developer Edition

  • 2 replies
  • 1 has this problem
  • 11 views
  • Last reply by cor-el

mojito
mojito
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I just installed the Developer Edition and am unable to load any https pages. I get a 'This Connection is Untrusted' error (Error code: sec_error_unknown_issuer) . My normal install of FF works fine as do other browsers. I don't usually get the Add an exception option though when I do, the site then loads without the styling. Time and date are correct and I've tried changing the proxy settings but no joy...

I just installed the Developer Edition and am unable to load any https pages. I get a 'This Connection is Untrusted' error (Error code: sec_error_unknown_issuer) . My normal install of FF works fine as do other browsers. I don't usually get the Add an exception option though when I do, the site then loads without the styling. Time and date are correct and I've tried changing the proxy settings but no joy...

All Replies (2)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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If you are comparing Firefox 36 and Firefox 39 there may well be changes applicable to some sites that use older encryption technologies. However, it's more likely that you are using a separate profile that is not yet set up to work with your security software's filtering of secure connections. For example, avast! 2015, BitDefender, ESET, and Kaspersky. Does that sound like a possibility?

If so, as a shortcut, you could copy the cert8.db file from your regular profile folder to the new profile folder so that all the certificates you have trusted in your regular profile would now be trusted in your new profile. Or we could assist in looking up the instructions for your security software.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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I assume that you have this issue on the Mac computer that you use?

Who is the issuer of the certificate?

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 and see who is the issuer

You can inspect the certificate chain in Details tab of the Certificate Viewer.