This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Rohkem teavet

How to fix Error code: SEC_ERROR_REUSED_ISSUER_AND_SERIAL

  • 2 vastust
  • 1 on selline probleem
  • 4 views
  • Viimati vastas Fran237

more options

I am getting this error on several sites, "Your certificate contains the same serial number as another certificate issued by the certificate authority. Please get a new certificate containing a unique serial number. Error code: SEC_ERROR_REUSED_ISSUER_AND_SERIAL". I see this has been an issue for many years but have not been able to find an answer. I have never set any certificate exemptions. Chrome works fine with the problematic sites so I don't think there is an issue with my router. Thanks for any help, I can't wait to stop using chrome.

I am getting this error on several sites, "Your certificate contains the same serial number as another certificate issued by the certificate authority. Please get a new certificate containing a unique serial number. Error code: SEC_ERROR_REUSED_ISSUER_AND_SERIAL". I see this has been an issue for many years but have not been able to find an answer. I have never set any certificate exemptions. Chrome works fine with the problematic sites so I don't think there is an issue with my router. Thanks for any help, I can't wait to stop using chrome.

All Replies (2)

more options

You can try to rename/remove the cert8.db file in the Firefox profile folder with Firefox closed.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

more options

Thanks for replying. I have tried removing that and another cert... file, restarting and nothing changes.