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firewall SSL certificate , SEC_ERROR_REUSED_ISSUER_AND_SERIAL

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

SohX
SohX
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Dears, i have renewed our corporate security certificate on microsoft certificate authority server, and imported it into our firewall like the old certificate. however, we imported the certificate into firefox , but when anyone try to connect to any https website , it returns this error SEC_ERROR_REUSED_ISSUER_AND_SERIAL or Your connection is not secure .

even tho the same certificate is working properly on chrome and IE, but we need firefox.

troubleshooting steps:

1- i have changed security.enterprise_roots.enabled; from false to true 2- security.ssl3.dhe_rsa_aes_256_sha; changed from true to false 3- security.ssl3.dhe_rsa_aes_128_sha; changed from true to false

but it doesnt fix our issue. note: firefox ver 58.0.2 and 58.0.1.

Dears, i have renewed our corporate security certificate on microsoft certificate authority server, and imported it into our firewall like the old certificate. however, we imported the certificate into firefox , but when anyone try to connect to any https website , it returns this error SEC_ERROR_REUSED_ISSUER_AND_SERIAL or Your connection is not secure . even tho the same certificate is working properly on chrome and IE, but we need firefox. troubleshooting steps: 1- i have changed security.enterprise_roots.enabled; from false to true 2- security.ssl3.dhe_rsa_aes_256_sha; changed from true to false 3- security.ssl3.dhe_rsa_aes_128_sha; changed from true to false but it doesnt fix our issue. note: firefox ver 58.0.2 and 58.0.1.

All Replies (2)

FredMcD
FredMcD
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There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connections and send their own certificate.

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

http://kb.mozillazine.org/Error_loading_websites

https://www.bing.com/search?q=web+site+access+denied

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Try to rename/remove cert9.db and when present cert8.db 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.