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RSA certificate SEC_ERROR_UNKNOWN_ISSUER on Windows

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  • Igcine ukuphendulwa ngu cor-el

kki-firstclass
kki-firstclass
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We bought and installed a Comodo RSA positivessl certificate on our Server. When we enter our domain into the browser the certificate is accepted with Firefox 55.0.3 on Mac But ther are still some issues with Firefox on Windows. Somtimes we get the error "sec error unknown issuer" with a FireFox browser under Windows. We installed the same version of FireFox (55.0.3) and on one computer the certificate is working and on the other one we get the unknowen issuer error and have to accept the certificate manually. Does anyone know how to solve this problem?

We bought and installed a Comodo RSA positivessl certificate on our Server. When we enter our domain into the browser the certificate is accepted with Firefox 55.0.3 on Mac But ther are still some issues with Firefox on Windows. Somtimes we get the error "sec error unknown issuer" with a FireFox browser under Windows. We installed the same version of FireFox (55.0.3) and on one computer the certificate is working and on the other one we get the unknowen issuer error and have to accept the certificate manually. Does anyone know how to solve this problem?

All Replies (2)

philipp
philipp
  • Moderator
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you'll have to install all the proper intermediate certs for your site... https://support.comodo.com/index.php?/Knowledgebase/Article/View/241/0/my-certificate-says-it-has-a-nonvalid-digital-signature-what-can-cause-this

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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