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Can't fix SEC_ERROR_REUSED_ISSUER_AND_SERIAL as described

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  • Last reply by FredMcD

Hi all,

while playing (or better "fighting"...) with a linux docker container on Win10/WSL2/Ubuntu for using the MS spfx tool chain, I generated a SEC_ERROR_REUSED_ISSUER_AND_SERIAL in FF85.0/Win10 by first setting up a certificate exception for a dev-cert (https://localhost:4321) and then have the certificate re-created.

As described the support article [https://support.mozilla.org/en-US/kb/Certificate-contains-the-same-serial...], I removed all certificate exceptions for localhost:* and deleted the "gulp" authority in options/security/certificates.

Unfortunately, the SEC_ERROR_REUSED_ISSUER_AND_SERIAL persists even after a restart of firefox.

Any help is very much appreciated...

Thanks & greetings Markus Fehn

Hi all, while playing (or better "fighting"...) with a linux docker container on Win10/WSL2/Ubuntu for using the MS spfx tool chain, I generated a SEC_ERROR_REUSED_ISSUER_AND_SERIAL in FF85.0/Win10 by first setting up a certificate exception for a dev-cert (https://localhost:4321) and then have the certificate re-created. As described the support article [[https://support.mozilla.org/en-US/kb/Certificate-contains-the-same-serial-number-as-another-certificate]], I removed all certificate exceptions for localhost:* and deleted the "gulp" authority in options/security/certificates. Unfortunately, the SEC_ERROR_REUSED_ISSUER_AND_SERIAL persists even after a restart of firefox. Any help is very much appreciated... Thanks & greetings Markus Fehn

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