Firefox error codes

14 codes — tap one for its meaning, causes, and fix steps.

• MOZILLA_PKIX_ERROR_MITM_DETECTEDFirefox detected a likely man-in-the-middle attack on this connection
• MOZILLA_PKIX_ERROR_SELF_SIGNED_CERTThe certificate is self-signed and not issued by a trusted certificate authority
• SEC_ERROR_BAD_DERThe certificate contains invalid DER-encoded data and cannot be parsed
• SEC_ERROR_CERT_SIGNATURE_ALGORITHM_DISABLEDThe certificate uses a signature algorithm that Firefox has disabled for security reasons
• SEC_ERROR_EXPIRED_CERTIFICATEThe server's certificate has expired and the connection cannot be secured
• SEC_ERROR_INADEQUATE_KEY_USAGEThe certificate is being used for a purpose not permitted by its key usage extension
• SEC_ERROR_OCSP_FUTURE_RESPONSEThe OCSP certificate status response is dated in the future
• SEC_ERROR_OCSP_INVALID_SIGNING_CERTThe certificate that signed the OCSP response is not trusted
• SEC_ERROR_REUSED_ISSUER_AND_SERIALA different certificate with the same issuer and serial number was already seen
• SEC_ERROR_REVOKED_CERTIFICATEThe certificate has been revoked by the authority that issued it
• SEC_ERROR_UNKNOWN_ISSUERFirefox does not recognize the authority that signed the certificate
• SSL_ERROR_BAD_CERT_DOMAINThe certificate is valid but was issued for a different hostname
• SSL_ERROR_NO_CYPHER_OVERLAPFirefox and the server could not agree on any shared encryption algorithms
• SSL_ERROR_RX_RECORD_TOO_LONGThe TLS record Firefox received was larger than the protocol allows