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certificate error


When I go to one of our development sites, I get this error: Secure connection failed An error occurred during a connection to xxx.xxx.com Peer's certificate has an invalid signature (Error code: sec_error_bad_signature) . I do not have the option to add an excpetion anymore, but we used to be able to navigate there. I'm running 3.6.13.

Additional System Details

Sites Affected


Installed Plug-ins

  • Adobe PDF Plug-In For Firefox and Netscape "9.4.1"
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Default Plug-in
  • Google Update
  • Shockwave Flash 10.1 r82
  • Adobe Shockwave for Director Netscape plug-in, version 11.5
  • GEPlugin
  • Next Generation Java Plug-in 1.6.0_23 for Mozilla browsers
  • 4.0.51204.0
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • Version 1.1.5, copyright 1996-2010 The VideoLAN Teamhttp://www.videolan.org/


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv: Gecko/20101203 Firefox/3.6.13

More Information

dj.si 0 solutions 3 answers

I'm also using Firefox 3.6.13 and had the same problem. This issue can be solved simply by changing Firefox's configuration - it's NOT necessary to install any Firefox add-ons to do this, even though internet searches will list various add-ons for fixing this problem.

This is how it's done:

- Open a new Firefox window, and type this into the address/URL:


- You'll probably see a warning that changing the config can be dangerous. Click the button to accept the warning and proceed, but BE CAREFUL from here on!

- A table will appear showing various Firefox settings ("Preference Names") and their current values.

- In the Filter box type: broswer.xul

- There should now be a shorter list of settings, including one named browser.xul.error_pages.expert_bad_cert with a value of false.

- Right-click on browser.xul.error_pages.expert_bad_cert and select Toggle. The value will change to true.

- Exit completely from Firefox (i.e. close all windows), and then restart it.

The next time you visit a secure site where there is a problem with its certificate, the certificate error page will show a button that allows the site to be added as an exception, and then you'll be able to proceed and view the site.

WARNING: If Firefox warns that there is a problem with a site's certificate, proceed only if:

a) you are 100% certain that it's safe, or

b) you accept the risks!

Certificate warnings should definitely NOT appear on any sites dealing with money/transactions, e.g. online shopping, online banking, etc.

Hope this helps!


pamjustice 0 solutions 1 answers

This doesn't always seem to work. I still get the same error and there is no button to allow me to add this site as an exception I am using version 3.6.18 and followed these instructions carefully but the same error page described here comes up when I tried to access my https site.

Modified by pamjustice

dj.si 0 solutions 3 answers

I am now using v3.6.18 as well. I have just tested this again, and it's working fine. I would suggest trying the following:

- Make sure every Firefox window has been closed

- Start Firefox in Safe Mode: Click Start -> Programs -> Mozilla Firefox -> Mozilla Firefox (Safe Mode)

- Go to about:config and ensure that the value of browser.xul.error_pages.expert_bad_cert is set to true, as described above

- Close the Firefox window and reboot your computer

- Start Firefox in Safe Mode again and check the setting of browser.xul.error_pages.expert_bad_cert - hopefully it will still be true

- Try opening the https page that you want to access and see if the button to add an exception is now available

- If that works, close the Firefox window, then restart Firefox normally (i.e. not in Safe Mode) and try the https page again

Hope that helps!


Phil 0 solutions 1 answers

Frustrating, tried all the above to no avail, but in the end after some searching found I had to import a versign certificate: https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&id=AR1514

talamortis 0 solutions 1 answers

Make sure your date and time is correct i had the same problem and thats how i fixed this