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Troubleshooting error code "SEC_ERROR_UNKNOWN_ISSUER"

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Hi, I recently re-installed firefox on my windows 10 laptop only to find that google no longer works as a webpage, the error message titled 'your connection is not secure' replacing my usual homepage. I've resorted to using duckduckgo as a temporary search engine, but every now and then the message returns with that too! Previous articles I've read concerning this issue suggest anti-virus software might be to blame, but I've already checked my bullguard software and there doesn't appear to be any issue of it blocking google (or any other site, for that matter). Any help would be much appreciated as I'd rather not revert back to microsoft edge...!

Hi, I recently re-installed firefox on my windows 10 laptop only to find that google no longer works as a webpage, the error message titled 'your connection is not secure' replacing my usual homepage. I've resorted to using duckduckgo as a temporary search engine, but every now and then the message returns with that too! Previous articles I've read concerning this issue suggest anti-virus software might be to blame, but I've already checked my bullguard software and there doesn't appear to be any issue of it blocking google (or any other site, for that matter). Any help would be much appreciated as I'd rather not revert back to microsoft edge...!

Kaikki vastaukset (4)

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hi, have you already configured bullguard like it's recommended in our support article on the subject? if the troubles continue after that, please give us more information about the error by clicking on the error code, copying the text to the clipboard and then pasting it here into a reply in the forum like shown in the screenshot.

thank you!

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Hi, I followed the article suggestions but the error code continued to come up: https://www.google.com/

Peer's Certificate issuer is not recognised.

HTTP Strict Transport Security: false HTTP Public Key Pinning: true

Certificate chain:


BEGIN CERTIFICATE-----

MIIDWjCCAkKgAwIBAgIIU4Px/idbvgswDQYJKoZIhvcNAQELBQAwIjEgMB4GA1UE AxMXTWljcm9zb2Z0IEZhbWlseSBTYWZldHkwHhcNMTcxMjEzMTMwOTQxWhcNMTgw MzA3MTMwMTAwWjBoMQswCQYDVQQGEwJVUzETMBEGA1UECAwKQ2FsaWZvcm5pYTEW MBQGA1UEBwwNTW91bnRhaW4gVmlldzETMBEGA1UECgwKR29vZ2xlIEluYzEXMBUG A1UEAwwOd3d3Lmdvb2dsZS5jb20wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK AoIBAQDUkoyhWwYyOJVsPWAMlQInnGcnW9MHNL3kN0h6e/Yzz2k5ohokWED/0zCW CaB3wGX7NPd97BiD0W1Dtqn+UB/blsk+ZrMtuNY3ejRw6qz++Nlc37Vf4Niw4T8H 6f+h665P95FIx/JVzpJPYsSjmzDxaNLcMEe2P2vcLPxqvtsG9OGxiOTo1s6B1aDC vc8kU4RyggTKnzIN5np/EeMeHVzrlbkTpHfFKrot0IC71eqLSZQvmc91zxjfL2/b tpKrZJA/iumTijaafPV+gMYn8ERvQoGXRs8vzF+PNPk6VMNIbmLBxHlKrotlIB9x dAihuTq6XDQMxcxK0T8NGmlC0QFbAgMBAAGjTjBMMBkGA1UdEQQSMBCCDnd3dy5n b29nbGUuY29tMAwGA1UdEwEB/wQCMAAwIQYDVR0gBBowGDAMBgorBgEEAdZ5AgUB MAgGBmeBDAECAjANBgkqhkiG9w0BAQsFAAOCAQEARCuLzixPkjveKFkowq40pWJa CqdBsOhSYiaBRw8h9O1NJFR/1jmD3EIHjHC2w7FVgT7XUzxni+trv2J77QTZVZ2M rsdmyXXuLcHhDUIdpXhSpMUOYqwXMbwc0ZUxYQLOlDVquahtcS+xWE7AxyR8F/7P dW618LM55rIB+TwzW+8DtRFXPp8RpvtXZsLL/8+b7+zu5vKmnjChfArSsFXiiMeY uTST5489Z4U3NhHFflw6mpEclyopzxnPI29ULwIfu70Qi8kDjQBWJdUjw+XDBuue hZNBr8WpSpQ3EwtpLtqByKDa5z3I68uKK861sojxgwUHgXr2EjkyN+9fQ72+CQ==


END CERTIFICATE-----


Thank you for your help!

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Please uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files and C:\Program Files(x86) Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 57.0.4 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Thank you for the certificate. The interloper generating the fake certificate is Microsoft Family Safety which you may need to reconfigure, either by turning it off or reconfiguring what different users are allowed to do. If this is a shared computer, you certainly should discuss that with the other users before making changes.