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Red screen locking Firefox saying Firefox_Critical_Error

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I am getting a solid red screen with screeching sound saying a web site is trying to do something to my computer and that it's a FIREFOX CRITICAL ERROR and I need to call help desk. The only way I have found to close the window is to open Task Manager and close Firefox. Sometimes after rebooting the page will go away for a period of time but it always comes back. HELP! How do I get rid of this monster? The Windows 10 Virus scanner won't clear it and neither will Malwarebytes malware scanner.

Thank you, Jake

I am getting a solid red screen with screeching sound saying a web site is trying to do something to my computer and that it's a FIREFOX CRITICAL ERROR and I need to call help desk. The only way I have found to close the window is to open Task Manager and close Firefox. Sometimes after rebooting the page will go away for a period of time but it always comes back. HELP! How do I get rid of this monster? The Windows 10 Virus scanner won't clear it and neither will Malwarebytes malware scanner. Thank you, Jake
Attached screenshots

Chosen solution

When you get a scam page that shows that two-line Authentication Required dialog, and you cancel it, usually the page will reload and show it again. To break the cycle, tap the Esc key several times in a row quickly. That should cancel the dialog AND the reload. Then you can easily close the tab.

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It’s obvious that this page, as with any page containing a barely readable domain name, is a hoax, trying to trick you into calling a phone number or in this case, enter some credentials. Of course, don’t do this.

You can report the page if you like - see Avoid and report Mozilla tech support scams for more info.

If you keep seeing this page, scan your system for malware.

You can try these free programs to scan for malware, which work with your existing antivirus software:

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista if you don't already have one. Windows 8/10 have antivirus protection built-in.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

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If it's like the fake FBI/Interpol browser lock page, This add-on can stop such pages; https://addons.mozilla.org/en-US/firefox/addon/disallow-script-button/ disallow Script Button

The Disallow Script button looks like a letter "M" and the title is the Minus Script, drag and drop the button on a toolbar. If the button is not displayed then nothing operates, except rules for plugins.


Another way out of the trap is to (force it if needed) Close Firefox. Wait about 20 seconds for Firefox to finish closing. Right-click on the Firefox icon and select Open New Window. +++++++++++++++++++++++++++++++++ Sometimes this works. If it opens, close it by Menu > File > Exit. This will flush out that web page from the Session Store.

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I don't think that add on would help me. When this screaming red page pops up nothing on my screen is operable. I can't click the X to close anything. I can't move to another tab. Nothing. Like I say the only way I have found to get out of it is ctrl/alt/delete to bring up Task Manager to shut down Firefox. Surely there must be a way to remove this thing from my computer.

Jake

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FredMcD said

Another way out of the trap is . . . . . .
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Chosen Solution

When you get a scam page that shows that two-line Authentication Required dialog, and you cancel it, usually the page will reload and show it again. To break the cycle, tap the Esc key several times in a row quickly. That should cancel the dialog AND the reload. Then you can easily close the tab.