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I am not able to open google, youtube and facebook type major websites when i will to open it will show Error code: SEC_ERROR_UNKNOWN_ISSUER "

  • 5 प्रत्युत्तर
  • 11
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  • के द्वारा अंतिम प्रतियुतर philipp

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I am not able to open google, YouTube and Facebook type major websites when I will open it will show Error code: SEC_ERROR_UNKNOWN_ISSUER "

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites

Your article will give only that particular antivirus solution information how to solve this issue, but what to do if I am using other antivirus software product like Quick Heal, Norton and other different antivirus which you have not mentioned in the article. I am using Quick Heal Antivirus Software. So please give me solution to solve this problem.

I am not able to open google, YouTube and Facebook type major websites when I will open it will show Error code: SEC_ERROR_UNKNOWN_ISSUER " How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites Your article will give only that particular antivirus solution information how to solve this issue, but what to do if I am using other antivirus software product like Quick Heal, Norton and other different antivirus which you have not mentioned in the article. I am using Quick Heal Antivirus Software. So please give me solution to solve this problem.

चुने गए समाधान

thank you - so apparently you have malware dubbed "my web shield" on your system that is intercepting all secure connections.

  1. please go to the windows control panel / programs and remove all toolbars or potentially unwanted software from there.
  2. then run a full scan of your system with different security tools like the free version of malwarebytes & adwcleaner, which are specialised in adware and browser hijackers.

Troubleshoot Firefox issues caused by malware

संदर्भ में यह जवाब पढ़ें 👍 1

All Replies (5)

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hi, a solution depends on the individual circumstances - so please give us more information about the error like shown in the screenshot by clicking on the error code, copying the text to the clipboard and then pasting it here into a reply in the forum.

thank you!

How to troubleshoot security error codes on secure websites

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I am attaching the file in which error have been mentioned.

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no, please don't attach a screenshot (nobody is going to transcribe that information from a picture), but copy/paste it in text form directly into a reply here instread...

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I am sending you a error mentioned in the page Your connection is not secure

The owner of www.youtube.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.

This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate.

Learn more…

Report errors like this to help Mozilla identify and block malicious sites

www.youtube.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: SEC_ERROR_UNKNOWN_ISSUER https://www.youtube.com/


Peer’s Certificate issuer is not recognized.


HTTP Strict Transport Security: false

HTTP Public Key Pinning: true


Certificate chain:



BEGIN CERTIFICATE-----

MIIGljCCBX6gAwIBAgIRAJB2XTv8/mX8jESsTx+bpNwwDQYJKoZIhvcNAQELBQAw

JzELMAkGA1UEBhMCRU4xGDAWBgNVBAMMD015IFdlYiBTaGllbGQgMjAeFw0xNzA1

MjQxNzEzMDBaFw0xNzA4MTYxNzEzMDBaMGYxCzAJBgNVBAYTAlVTMRMwEQYDVQQI

DApDYWxpZm9ybmlhMRYwFAYDVQQHDA1Nb3VudGFpbiBWaWV3MRMwEQYDVQQKDApH

b29nbGUgSW5jMRUwEwYDVQQDDAwqLmdvb2dsZS5jb20wgZ8wDQYJKoZIhvcNAQEB

BQADgY0AMIGJAoGBAMUBQftUiuSKd/lKSwOTAELHXjvsOqT4JnW6QPKVSqvNlVdH

kyhwxdqCBEvMLrxNFMlIZUz3WxRnYkBLXAkMMUcpkHHeaxQDMFL6csQrjA8je1X2

TByWC87XVRxBBlIL5qFGH+0sHo8rj74MOJ7ig5cEpFAm5zMZOtBBkS/VwxolAgMB

AAGjggQAMIID/DCCA8sGA1UdEQSCA8IwggO+ggwqLmdvb2dsZS5jb22CDSouYW5k

cm9pZC5jb22CFiouYXBwZW5naW5lLmdvb2dsZS5jb22CEiouY2xvdWQuZ29vZ2xl

LmNvbYIGKi5nLmNvgg4qLmdjcC5ndnQyLmNvbYIWKi5nb29nbGUtYW5hbHl0aWNz

LmNvbYILKi5nb29nbGUuY2GCCyouZ29vZ2xlLmNsgg4qLmdvb2dsZS5jby5pboIO

Ki5nb29nbGUuY28uanCCDiouZ29vZ2xlLmNvLnVrgg8qLmdvb2dsZS5jb20uYXKC

DyouZ29vZ2xlLmNvbS5hdYIPKi5nb29nbGUuY29tLmJygg8qLmdvb2dsZS5jb20u

Y2+CDyouZ29vZ2xlLmNvbS5teIIPKi5nb29nbGUuY29tLnRygg8qLmdvb2dsZS5j

b20udm6CCyouZ29vZ2xlLmRlggsqLmdvb2dsZS5lc4ILKi5nb29nbGUuZnKCCyou

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ggsqLmdvb2dsZS5wdIISKi5nb29nbGVhZGFwaXMuY29tgg8qLmdvb2dsZWFwaXMu

Y26CFCouZ29vZ2xlY29tbWVyY2UuY29tghEqLmdvb2dsZXZpZGVvLmNvbYIMKi5n

c3RhdGljLmNugg0qLmdzdGF0aWMuY29tggoqLmd2dDEuY29tggoqLmd2dDIuY29t

ghQqLm1ldHJpYy5nc3RhdGljLmNvbYIMKi51cmNoaW4uY29tghAqLnVybC5nb29n

bGUuY29tghYqLnlvdXR1YmUtbm9jb29raWUuY29tgg0qLnlvdXR1YmUuY29tghYq

LnlvdXR1YmVlZHVjYXRpb24uY29tggcqLnl0LmJlggsqLnl0aW1nLmNvbYIaYW5k

cm9pZC5jbGllbnRzLmdvb2dsZS5jb22CC2FuZHJvaWQuY29tghtkZXZlbG9wZXIu

YW5kcm9pZC5nb29nbGUuY26CHGRldmVsb3BlcnMuYW5kcm9pZC5nb29nbGUuY26C

BGcuY2+CBmdvby5nbIIUZ29vZ2xlLWFuYWx5dGljcy5jb22CCmdvb2dsZS5jb22C

Emdvb2dsZWNvbW1lcmNlLmNvbYIYc291cmNlLmFuZHJvaWQuZ29vZ2xlLmNuggp1

cmNoaW4uY29tggp3d3cuZ29vLmdsggh5b3V0dS5iZYILeW91dHViZS5jb22CFHlv

dXR1YmVlZHVjYXRpb24uY29tggV5dC5iZTAMBgNVHRMBAf8EAjAAMB0GA1UdJQQW

MBQGCCsGAQUFBwMBBggrBgEFBQcDAjANBgkqhkiG9w0BAQsFAAOCAQEAzPbngBBW

qLJt1eiqSBZuQnRSo6Zs+O1PNZFyRqKU859HB7Fy01GGJFhl2oqb1SS4pbl7GmBM

tx6nX+rDBHaHvp1m+ccH3QuDhvqtyEeuauLn5zdHTx7No8UmSIrZ7u0t/YO23HFW

3NECSJRc5tIZTw/jrVyTj4SnUgcsZauJSsB3t4uKTRSzL0LP4EPcsEU+UrWPHp2d

+wO5yZ2eqDLS7HNvZqMi6Bwo/XQungPsezaUvD6vCfdGGVo5NWKREVvgBh5rJI/7

jQH2uT9uXBWacZ6kJfeKSExizO50j2b/+WXU53gdZgOVC+iquBlvH+E95zYXiG5G

wsacTmiE4eV5mA==


END CERTIFICATE-----
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चयनित समाधान

thank you - so apparently you have malware dubbed "my web shield" on your system that is intercepting all secure connections.

  1. please go to the windows control panel / programs and remove all toolbars or potentially unwanted software from there.
  2. then run a full scan of your system with different security tools like the free version of malwarebytes & adwcleaner, which are specialised in adware and browser hijackers.

Troubleshoot Firefox issues caused by malware