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Firefox won't load https pages; gives security warning and won't accept an exception.

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  • 40 have this problem
  • 3 views
  • Last reply by laknox

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I've been having issues with Firefox and certain sites for about a year, and it's localized to my personal laptop. I have no issues when using my desktop at work or my dad's laptop at his house. Certain sites will simply return a text-style page; no html. Other sites give me a security certificate warning and FF won't accept an exception for that site, either by clicking on the button or manually entering the site as an exception. Tonight, GOOGLE won't even load! Why it's trying to load on an https server, I don't know, however. Several other sites have also started not loading and are also trying to load to a secure server.

I've been having issues with Firefox and certain sites for about a year, and it's localized to my personal laptop. I have no issues when using my desktop at work or my dad's laptop at his house. Certain sites will simply return a text-style page; no html. Other sites give me a security certificate warning and FF won't accept an exception for that site, either by clicking on the button or manually entering the site as an exception. Tonight, GOOGLE won't even load! Why it's trying to load on an https server, I don't know, however. Several other sites have also started not loading and are also trying to load to a secure server.

Chosen solution

Do you use Kaspersky, AVAST 2015, ESET, BitDefender, or Microsoft Family Security? These are among the most popular security programs that have a feature to intercept your web connections and filter your traffic. When it is a secure site, in order to be able to decrypt and inspect your communications, the software needs to present a fake certificate to Firefox. Sometimes the software is not able to set up Firefox for this, or if you use Firefox's Reset feature, the trust is broken and needs to be set up again.

Unfortunately, the same symptoms can appear with some malware.

If you look at the second half of phlipp's post, you see where you can inspect the "Issued by" section of the certificate. This usually helps identify the culprit. Can you take a look and report back on what you find?

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All Replies (9)

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hello, first please make sure that the date, time & timezone are set correctly on your system. if this doesn't solve the issue (or it is already set properly), a possible solution depends on different factors:

  • what is the error code shown under technical details on the error page?

in case the error code equals sec_error_unknown_issuer, please attempt to add an exception on the bottom of the error page (don't add it for real!) & inspect the certificate (see the screenshot attached for instructions):

  • which issuer information does the certificate contain?

thank you!

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

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idm.east.cox.net uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)

This is copied from the error page when trying to log in to MY OWN ISP ACCOUNT PAGE! At this stage, I'm ready to dump FF lock, stock and barrel, if I can't even log into my own ISP page! I've tried disabling =all= addons and extensions, rebooting my system, run multiple system scans with several different AV and anti-malware programs and it's =still= fucking up! I've been a loyal FF user since ver. 2 days and this is just ludicrous.

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Seçilmiş Həll

Do you use Kaspersky, AVAST 2015, ESET, BitDefender, or Microsoft Family Security? These are among the most popular security programs that have a feature to intercept your web connections and filter your traffic. When it is a secure site, in order to be able to decrypt and inspect your communications, the software needs to present a fake certificate to Firefox. Sometimes the software is not able to set up Firefox for this, or if you use Firefox's Reset feature, the trust is broken and needs to be set up again.

Unfortunately, the same symptoms can appear with some malware.

If you look at the second half of phlipp's post, you see where you can inspect the "Issued by" section of the certificate. This usually helps identify the culprit. Can you take a look and report back on what you find?

Modified by jscher2000 - Support Volunteer

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Also make sure that you have updated to the latest Firefox 33.1.1 release.

  • Help > About

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

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I find it more than passing strange that http://www.google.com keeps wanting to go to https://www.google.com, a =secure= connection. Since when did google use a secure connection? I still have the issue that many others have, in that FF won't save security exceptions, even manually entered ones. My FF is the latest version as it auto-updates. I =do= use Avast, but even with the Avast add-on disabled, and a reboot, FF still won't load these pages. Even pages that loaded fine in the morning, wouldn't load 8 hours later in the evening!

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Google has been redirecting to HTTPS for a long time now...

The Avast intercept is not part of the avast! Online Security extension, it's part of avast! Web Shield which runs outside of Firefox. I think you have two options:

(1) Disable HTTPS scanning in Avast Web Shield; or

(2) Import Avast's certificate into Firefox's "Authorities" tab so Firefox accepts its fake certificates (there might be an automated way AVAST intended for you to do this, or you might need to export from IE and then import into Firefox)

Here is some discussion on avast!'s forum about how this is supposed to work: Issues and questions on HTTPS Scanning - Avast Internet 2015

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Well, it seems that a reset of FF has, so far, solved my problems. I can get into Google and log into my bank, which I haven't been able to do for months. Sounds like something Mozilla needs to address, since so many people have the issue.

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Thanks for the tip. If Avast keeps acting up, I'll simply get something else. They're not the only AV app on the block. For now, things are back to normal. Maybe Flash might quit crashing, too...and then I woke up.

Modified by laknox

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No such luck on the Flash issue. FF just crashed on foxnews.com... Why can't people just dump that junk?