There is security software like Avast and Kaspersky and BitDefender and ESET that intercept secure connections and send their own certificate.

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

https://support.mozilla.org/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

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

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

Thanks for the quick response!

Submitted Crash Reports from Safari, if that matters. Deleted and reinstalled Firefox already and it had no reports left. Report ID Date Submitted bp-73a2c246-69ca-49b9-8fa7-2acad2151202 12/1/15 7:05 PM 85F9A7BA-2970-49C0-8023-2EC464A7FE8F 3/31/15 11:42 AM E06A90E0-3168-434A-8BE6-6E78C43D4C2F 2/12/15 9:03 PM

Also, upon further inspection I noticed a few more things. It is only the https sites, and is on both Safari and Firefox.

Error code: SEC_ERROR_UNKNOWN_ISSUER.

I cannot get through on Firefox to a https site. I mostly get through on Safari, but also sometimes get denied. On my other computer, HTTPS sites have been fine.

Cleared cache and history already.

I made the other login and started downloading my normal stuff. I recall an Adobe install, a Firefox one (before realizing most apps came over with it) and then I got a Old Firefox folder on my desktop. I then started my add-ons. Here is the list: uBlock Origin, HTTPS Everywhere, and the new one -- Random Agent Spoofer. That is the only new thing on the computer when the internet got messed up.

So (I think) I deleted all of the add-ons in attempt to fix it (again not sure). However, I cannot even open up the FireFox add-ons page because it is insecure.

While typing, I noticed pretty much the only thing I cannot get to on Safari is Avast.com.

Reinstalled FireFox twice, and also did the restart feature inside of it.

Thanks ago for helping.

could you give us more information about the error by clicking on the error code, copying the text to the clipboard (like shown in the screenshot) and then pasting it here into a reply in the forum.

thank you!

Finally got it resolved. Kasperly finally finished its run, but found nothing. I went to restart the computer and had an install prompt come up. When it completed the issues were fixed.

Should I not attempt the same add-ons that I did last time?

BD0000 said

I went to restart the computer and had an install prompt come up

What got installed?

Should I not attempt the same add-ons that I did last time?

Try them one at a time.

Product Firefox Version 42.0 Build ID 20151029151421 Release Channel release OS OS X 10.9 OS Version 10.9.5 13F1134

https://support.mozilla.org/en-US/kb/update-firefox-latest-version 46.0.1

Some of your crash reports weren’t sent to the Mozilla Servers.

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

bp-73a2c246-69ca-49b9-8fa7-2acad2151202

Signature: shutdownhang | libsystem_kernel.dylib@0x15716

libsystem_kernel.dylib =  ? Word for Mac

This is for Sumo's Related Bugs 1272614 NEW --- Browser crashing while being restarted after an update