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How to fix Error code: SEC_ERROR_REUSED_ISSUER_AND_SERIAL

  • 2 replies
  • 1 has this problem
  • 5 views
  • Last reply by Fran237

Fran237
Fran237
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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)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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.

Fran237
Fran237 Question owner
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Thanks for replying. I have tried removing that and another cert... file, restarting and nothing changes.