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I receive error message "SEC-error_unknown_ISSUER". I have followed your support info. What now?

  • 4 replies
  • 4 have this problem
  • 18 views
  • Last reply by Jerilynn

Jerilynn
Jerilynn
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I have followed your instructions, un-installed and re-installed twice. I have disabled virus/malware, firewall, you name it and I have probably tried it. It won't go anywhere, I get the same message wherever I try to go. Is this new version incompatible with win 10? Please help me, I don't want to use Chrome or IE. I miss my Firefox.........

I have followed your instructions, un-installed and re-installed twice. I have disabled virus/malware, firewall, you name it and I have probably tried it. It won't go anywhere, I get the same message wherever I try to go. Is this new version incompatible with win 10? Please help me, I don't want to use Chrome or IE. I miss my Firefox.........

All Replies (4)

Shadow110
Shadow110
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Since uninstalled.... Have you done it this way : 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 : https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 57.0.2 with a Full Version Installer https://www.mozilla.org/firefox/all/

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

Jerilynn
Jerilynn Question owner
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I followed your instructions and I am receiving the error message that says "Website not secure, it is configured improperly". I tried amazon, facebook, twitter, wikipedia and my home page all with the same result. Using Chrome is close to torture, you know that?

Modified by Jerilynn

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Who is the issuer of the certificate?

You can click the "Advanced" button to expand this section and show extra details. If the certificate is not trusted because no issuer chain was provided (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and show the certificate chain. You can click "Copy text to clipboard" and paste this base64 encoded certificate chain text in a reply. That will allow us to details like the issuer of the certificate.

  • always be cautious when you get an 'Untrusted' error message
  • never create a permanent exception without investigating the cause and only use this to inspect the certificate
Jerilynn
Jerilynn Question owner
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The problem turned out to be my proxy settings, somehow they were changed. It is working beautifully, so if anyone else has this issue check your proxy settings. I am so happy I don't have to look at Chrome, IE or Edge again!!!!! Yippeeeee...........Thanks for your help and have a great day to all of you at Mozilla Love my firefox.