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When I try to login into my google or yahoo mail it give me a certificate error of MOZILLA_PKIX_ERROR_V1_CERT_USED_AS_CA.

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  • Last reply by cor-el

Saurabhdesai181
Saurabhdesai181
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When I try login into gmail or yahoo mail from firefox it gives me a certificate error of MOZILLA_PKIX_ERROR_V1_CERT_USED_AS_CA. Can you please check this issue ?

I tried to into gmail and yahoo mail from internet explorer and google chrome and it works. Can you please look into it ?

Thank You, Saurabh Desai

When I try login into gmail or yahoo mail from firefox it gives me a certificate error of MOZILLA_PKIX_ERROR_V1_CERT_USED_AS_CA. Can you please check this issue ? I tried to into gmail and yahoo mail from internet explorer and google chrome and it works. Can you please look into it ? Thank You, Saurabh Desai

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cor-el
cor-el
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  • Top 10 Contributor
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Try to rename the cert8.db file (cert8.db.old) and delete the cert_override.txt file in the Firefox profile folder to remove intermediate certificates and exceptions that Firefox has stored.

If that has helped to solve the problem then you can remove the renamed cert8.db.old file.

Firefox will automatically store intermediate certificates that servers send in the Certificate Manager for future use.

You can use this button to go to the current Firefox profile folder:

You can retrieve the certificate and check details like the issuer of the certificate and the certificate chain.

  • click "Advanced" to expand the error message
  • click "Add Exception" to open "Add Security Exception"

If this isn't possible then open the Certificate Manager and go to the Servers tab.

  • Options/Preferences -> Advanced -> Certificates: View Certificates 
-> Servers -> "Add Exception" button

Let Firefox retrieve the certificate -> "Get Certificate"

  • click the "View" button and inspect the certificate

You can see details like the issuer of the certificate and used intermediate certificates in the Details tab.