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This Connection is Untrusted error for many sites

  • 3 antwurd
  • 15 hawwe dit probleem
  • 10 werjeftes
  • Lêste antwurd fan Abinaya

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I installed the latest version of Firefox for Windows 8 with 2 add-ons; NoScript and AdBlock Plus. I get the untrusted connection error for the majority of sites I've tried to access: DuckDuckGo search engine, Verizon webmail, mail.google.com, my college email account, etc. I do not get this error when I access the same sites using either Internet Explorer on the Windows machine or Firefox on my Mac, so it seems to be some sort of problem with this version of firefox for this OS not being able to properly deal with certificates. How do I fix this problem?

I installed the latest version of Firefox for Windows 8 with 2 add-ons; NoScript and AdBlock Plus. I get the untrusted connection error for the majority of sites I've tried to access: DuckDuckGo search engine, Verizon webmail, mail.google.com, my college email account, etc. I do not get this error when I access the same sites using either Internet Explorer on the Windows machine or Firefox on my Mac, so it seems to be some sort of problem with this version of firefox for this OS not being able to properly deal with certificates. How do I fix this problem?

Alle antwurden (3)

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hello, first please make sure that the date & time is set correctly on your system.
if this doesn't solve the issue (or it is already set properly), could you tell us which error code is shown under technical details on the error message and when you inspect the certificate which issuer information it does contain (see screenshot)?

"This Connection is Untrusted" error message appears - What to do

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Note that some firewalls monitor (secure) connections and that programs like Sendori or FiddlerRoot can intercept connections and send their own certificate instead of the website's certificate.

Check out why the site is untrusted (click "Technical Details to expand that section) and if this is caused by a missing intermediate certificate then see if you can install this intermediate certificate from another source.

You can retrieve the certificate and check details like who issued certificates and expiration dates of certificates.

  • Click the link at the bottom of the error page: "I Understand the Risks"

Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate".

  • Click the "View..." button and inspect the certificate and check who is the issuer of the certificate.

You can see more Details like intermediate certificates that are used in the Details pane.

If "I Understand the Risks" is missing then this page may be opened in an (i)frame and in that case try the right-click context menu and use "This Frame: Open Frame in New Tab".


Check the connection settings.

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

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check your systems date and time. Set it correctly.