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Hy all,I can't access youtube.com. When I try Mozilla says:

Did Not Connect: Potential Security Issue

Firefox detected a potential security threat and did not continue to www.youtube.com because this website requires a secure connection.

What can you do about it?

www.youtube.com has a security policy called HTTP Strict Transport Security (HSTS), which means that Firefox can only connect to it securely. You can’t add an exception to visit this site.

The issue is most likely with the website, and there is nothing you can do to resolve it.

If you are on a corporate network or using anti-virus software, you can reach out to the support teams for assistance. You can also notify the website’s administrator about the problem.

ANY FIX? TNX!

Hy all,I can't access youtube.com. When I try Mozilla says: Did Not Connect: Potential Security Issue Firefox detected a potential security threat and did not continue to www.youtube.com because this website requires a secure connection. What can you do about it? www.youtube.com has a security policy called HTTP Strict Transport Security (HSTS), which means that Firefox can only connect to it securely. You can’t add an exception to visit this site. The issue is most likely with the website, and there is nothing you can do to resolve it. If you are on a corporate network or using anti-virus software, you can reach out to the support teams for assistance. You can also notify the website’s administrator about the problem. ANY FIX? TNX!

All Replies (3)

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Hello,

Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

  • Click the menu button Fx57Menu, click Help Fx57Help and select Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

  • On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
  • On Mac: Hold the option key while starting Firefox.
  • On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
    (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

Fx68SafeMode

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

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What virus software besides Win Defender are you running?

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Also, you can get more technical information if you click the "Advanced" button on the page. That should show:

(A) An error code such as SEC_ERROR_UNKNOWN_ISSUER

Searching by the exact error code can help in finding more relevant solutions. What is yours?

(B) A View Certificate link

The "Issued by" section of the unverifiable certificate usually is the most helpful one. It may identify a "man in the middle" of your connection. Let us know what you find (usually, Google is the signer of their own site certificates).