What is the computer system and Firefox?

http://www.ehow.com/how_11385212_troubleshoot-reset-connection-firefox.html

https://support.mozilla.org/en-US/kb/server-not-found-connection-problem

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

http://kb.mozillazine.org/Error_loading_websites

This Connection is Untrusted is sometimes caused because the computer system clock is wrong. Check the time / date / time zone settings.

Could you copy/paste the full error message into a reply message: https://support.mozilla.org/questions/1084660#question-reply

If it is a pop-up which cannot be selected, perhaps you can capture a screen shot instead. This article has tips on that: How do I create a screenshot of my problem? Please cut or blur out any sensitive/personal information in the image before attaching it to a reply.

It is possible that your firewall or other security software blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access to install for Firefox and the plugin-container process and the updater process.

See:

• https://support.mozilla.org/kb/Server+not+found
• https://support.mozilla.org/kb/Firewalls

• https://support.mozilla.org/kb/fix-problems-connecting-websites-after-updating

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) to see if that has effect.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/

Yes i can copy the message. Im using Windows 7 Ultimate and Firefox 4.0.3

Yes i can copy the message. Im using Windows 7 Ultimate and Firefox 40.0.3. i just got 41.0 im gonna test

This connection can not be trusted

You wanted to create a secure connection to the Firefox address www.google.com, but we can not assure the security of your connection.

Typically submit websites to connect to a secure page for the credibility of witness tuvastustunnused. These characteristics make it possible to establish that you are at the right website. Unfortunately it is not possible to verify the identity of the website. What are you supposed to do?

If you usually connect to this Web site to succeed, then the current error could mean that someone is trying to appear in this web page. In this case, you should not continue.

This site uses HTTP Strict Transport Security (HSTS) rule, which may be of use for this site only in Firefox secure connection. Therefore it is not possible to add an exception for this certificate.

all websites

Hi MegaHello, thank you for the additional information. Unfortunately that particular error page didn't list a specific error code, so we'll need you to investigate further.

When you get this for pretty much all secure sites, the problem usually is one of the following:

(1) Error in your system's date, time, or time zone, which throws off certificate validity checks. Sometimes allowing computers to use an internet-based time source can introduce this problem.

(2) Firefox not being set up to work with your security software that intercepts and filters secure connections. Products with this feature include Avast, BitDefender, ESET, Kaspersky; AVG has a Search Shield feature which can cause this error on search sites.

(3) Malware on your system intercepting secure connections.

So... which is it?

If you have any of those specific security products, that would be the first thing to check. We might be able to assist with specific next steps based on what you have if you tell us.

Alternately, you can examine the certificate to which Firefox is objecting to see whether the issuer information points to the culprit. Take my test page for example:

https://jeffersonscher.com/res/jstest.php

You should see an "I understand the risk" heading in the page. If you expand that section, you should find an Add Exception button. You don't need to complete the process of adding an exception (I suggest not adding one until we know this isn't a malware issue) but you can use the dialog to view the information that makes Firefox suspicious.

Click Add Exception, then View. If View is not enabled, try the Get Certificate button first. Then in the Certificate Viewer, look at the "Issued by" section. What do you find there, and/or under Certificate Hierarchy? I have attached a screen shot for comparison.