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SEC_ERROR_UNKNOWN_ISSUER on every website

  • 1 reply
  • 3 have this problem
  • 11 views
  • Last reply by FredMcD

Frozer
Frozer
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I get "Connection is not secure" on every website. Error code is SEC_ERROR_UNKNOWN_ISSUER. Certificate issuer on every website is "ffeb984503f19da0 2". Problem is only on Mozilla Firefox. I've tried to reinstall and refresh Mozilla without success. I don't have avast, kaspersky or others which have been causing same kind of problems. I've run three programs full virus/malware scans without any found threats. I'm pretty sure that that certificate issuer is the problem but I have no idea how to fix it or what causes it. Help please. Thank you!

I get "Connection is not secure" on every website. Error code is SEC_ERROR_UNKNOWN_ISSUER. Certificate issuer on every website is "ffeb984503f19da0 2". Problem is only on Mozilla Firefox. I've tried to reinstall and refresh Mozilla without success. I don't have avast, kaspersky or others which have been causing same kind of problems. I've run three programs full virus/malware scans without any found threats. I'm pretty sure that that certificate issuer is the problem but I have no idea how to fix it or what causes it. Help please. Thank you!
Attached screenshots

Modified by Frozer

All Replies (1)

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

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.cdn.mozilla.net/media/uploads/images/thumbnails/2017-06-07-08-34-22-cb6da3.png

https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER