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I've disabled all of my addons, cleared cache, and still youtube is broken for me. It works fine with Chrome still. Any ideas on how to fix? See attched screenshot.

Secure connection failed and Firefox did not connect Firefox Last updated: 01/16/2024 39% of users voted this helpful

This article explains why you may see a Secure Connection Failed or a Did Not Connect: Potential Security Issue error page, and what you can do.

   If you see a Warning: Potential Security Risk Ahead error page, see What do the security warning codes mean? and How to troubleshoot security error codes on secure websites.
   To troubleshoot other error messages, see Websites don't load - troubleshoot and fix error messages. 

Table of Contents

   Secure connection cannot be established
       Secure Connection Failed
       Did Not Connect: Potential Security Issue
   Website issues
       TLS version unsupported
       HSTS required
   Security software conflict
   Incorrect system clock
   Other secure connection issues

Secure connection cannot be established

When a website that requires a secure (HTTPS) connection tries to secure communication with your computer, Firefox cross-checks this attempt to make sure that the website certificate and the connection method are actually secure. If Firefox cannot establish a secure connection, it will display a Secure Connection Failed or Did Not Connect: Potential Security Issue error page. Secure Connection Failed

A Secure Connection Failed error page will include a description of the error and a Try Again button. There is no option to add a security exception to bypass this type of error.

Fx97SecureConnectionFailed ~~~ The url gives me this can you help please its not bitdefender total security blocking it I dont think https://support.mozilla.org/en-US/kb/secure-connection-failed-firefox-did-not-connect?as=u&utm_source=inproduct

I just tried to open Firefox and got the message "The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem". DO NOT redirect to this link

https://support.mozilla.org/en-US/kb/fix-bookmarks-and-history-will-not-be-functional?as=u&utm_source=inproduct&redirectslug=The+bookmarks+and+history+system+will+not+be+functional&redirectlocale=en-US

It is useless. I tried to restore 3953 items from a previous back up and received the message "Unable to process the backup file".

I am not interested in hearing how to prevent this problem in the future, because obviously creating backups do not work.

How do I check to see if the problem was caused by security software, even though I have not added anything?

I joined a couple facebook groups. Each offered a file tab with documents available for download.

I tried numerous times with firefox and it failed. Clicking the "Download" item on the ... menu caused the same files tab view and list to open in a new tab.

I hated to do it, but I dusted off M$ Internet Explorer, logged into FB and joined a group, clicked the Files tab, selected a file, clicked the 3 dots, menu popped up and I clicked "Download". Poof. The Save As popup appeared, the file was downloaded. Works as expected with IE.

Might there be a setting in FF that is blocking such downloads of PDF and .doc document files?

I realize Facebook doesn't have a spell check feature,but is there a way my browser, Firefox, which I already have spell check enabled can somehow spell check Facebook when I chat? Can someone help? Thank you.

Hello

Last week I deleted my browsing history, I had don't so since 2023, sadly I just found out that I need to restore a number of those close pages, I found the same topic on the site however it's from 2020 :

1. Click "Start" > "Search" > "Tools" > "Folder Options." 2. Click "View" > select "Show hidden files and folders" > uncheck "Hide extensions for known file types" and "Hide protected operating system files". 3. Click search in "All Files and Folders" in the C Drive > type index.dat in search bar > click "Search". 4. Download and install index.dat file reader on your PC if you don't have one. 5. Open index.dat file within the reader > Click on the Firefox browsing history you want to restore > Click "Restore". Then you can open your Firefox browser to check all your restored history now.

I followed the above steps until nr 5, it does not show me any data on firefox

Contrast disappears when I klick 'Login' eg. on 'https://www.elektor.de/'; other browsers are ok. AdGuard on or off makes no difference. Kind Regards [removed email from public]

Hi, I want to use dark background color theme in the Mozilla Firefox PDF viewer, read here https://support.mozilla.org/en-US/questions/1434510 but cannot find "userContent.css". My question is where can I find this file on a Windows 7 or Windows 10 installation?