I picked up some malware recently and one of the many annoyances it caused was problems with Firefox’s security settings. When visiting secure (https:) web sites Firefox would say “the connection is untrusted.” When I said I wanted to trust the site and add an exception for it I would get a “sec_error_untrusted_issuer” error. When I got past the errors and added the exception the site still wouldn’t work properly — I would only see a plain text version of the secure page without images, buttons, or formatting.
After many days of grief I finally found the answer in Mozilla’s bug database: https://bugzilla.mozilla.org/show_bug.cgi?id=583191 (and yes, I got the same error when visiting Mozilla’s site). I first tried the recommended troubleshooting steps without success. I then tried the following approach, recommended by Matthias Versen. (I did this with Firefox 3.6 and Windows 7.)
- Type the phrase about:support as a URL in the Firefox address bar.
- Click the button next to Profile Directory labeled “Open Containing Folder“. That will launch Windows Explorer.
- Close Firefox.
- Locate the file cert8.db in the Windows Explorer pane you opened in step 2 and move the file to a different location (like your desktop) or rename it.
- Start Firefox again.
All I can say is that it worked for me. Maybe it will help you.
Heather M. says
I’d been having this problem for quite some time. Thank you!
Robert says
You’re welcome! I hope the problem’s fixed.
Joe says
I ve bn having the same problem hoping am done with it. thankx
Alex in Toronto says
I started having this terribly annoying problem when I upgraded from Firefox 5.0 to 6.0. I upgraded to Aurora 7 and 8 with no resolution either in an attempt to fix the problem. I noticed that the error started when FF6 could not connect to the add-ons server after installation. Alas,It did not work for me fully the first time so I did it again and it appears to have stopped the flood of warnings dead . THANK YOU SO MUCH FOR POSTING THE SOLUTION.
Sarah in Virginia says
This was extremely helpful. My daughter called us from college with this problem and this fixed it. Thanks so much.
Hume's Bastard says
The cert8.db file just keeps reappearing as soon as I bring up the browser. I’ve tried three different solutions, including this, and the same thing happens. Thanks for the idea, but I’m nowhere near a solution still.
Robert says
HB – the cert8.db file should come back — but it should be back to its normal default settings. But if that’s not working I suggest asking on https://bugzilla.mozilla.org
Dejan says
Your article just helped me solve this annoying problem with Firefox 7 not allowing me to store my self-signed certificate in exceptions. Big thanks!
marc sitkin says
Thanks, that worked on my wifes mac!
Jim says
This was very very helpful and fixed my problem I have been having for years with Firefox.
Romy de Argentina says
Gracias!!! solucioné el problema
Paul_CZ says
Thank You! This solved my problem after installing Fx 9.0!
Rocdufer says
Thank you, it worked. Deleting cert8.db forces Firefox to create a new cert8.db, that degraded some how.
Sam101 says
Thank You.. Thank You. You saved my life!! I have been looking to fix problem with google for last few days. I remember I accidentally deleted some certificates while fixing other problem, since then I had this problem.
My gmail and anything related to google did not work properly. Either missing icons or missing entire maps or messed up site (picasaweb). Removing this CERT8.db fixed the problem. This means it will start fresh with the certification process. Hope that will not cause major issue.
Thanks again…