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I am getting constant msgs from FF 60 (64 bit) errorCode "SEC_ERROR_UNKNOWN_ISSUER"

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  • Last reply by FredMcD

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This is serious shit..FF refuses to allow me to log into https://sso.yealink.com/ OS is win7 64bit I've tried many options; disabling all add-ons, adding the url to ABP etc The report I am presented with is: ticket.yealink.com uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.

Error code: <a id="errorCode" title="SEC_ERROR_UNKNOWN_ISSUER">SEC_ERROR_UNKNOWN_ISSUER</a>

IE 10 has no issues with this url.

Where and how do I update the required certificates?

This is serious shit..FF refuses to allow me to log into https://sso.yealink.com/ OS is win7 64bit I've tried many options; disabling all add-ons, adding the url to ABP etc The report I am presented with is: ticket.yealink.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: <a id="errorCode" title="SEC_ERROR_UNKNOWN_ISSUER">SEC_ERROR_UNKNOWN_ISSUER</a> IE 10 has no issues with this url. Where and how do I update the required certificates?

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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


  • uses an invalid security certificate SSL_ERROR_BAD_CERT_DOMAIN
  • configured their website improperly

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

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I cannot see an answer in any of those links provided. I am using a registered premium version of Malwarebytes, have adding both url's as seen in this attached image. Windows throws no wobbles either. As far as I can see Malwarebytes has no issues with this site. I'd like to attached a screen dump I am confronted with after I signed into https://sso.yealink.com/

FYI this Yealink site is used to discuss owner config issues. Really appreciate any help offered.

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The bottom of my last post has instructions for that error.