If you get a pop-up message asking to update Firefox or plugins or scanning for malware then such a message is likely a scam and you should never respond to such an alert to avoid getting infected with malware.

• Only update Firefox via "Help > About" or by downloading and installing Firefox from the Mozilla server and never via a pop-up or link on a web page.
• Plugins should only be updated via the plugin itself or by visiting the home page of the plugin.

is there a way to keep this from happening or a way to report it.it fills the whole screen and have to shut down browser .

Are you saying the comes up when you start the browser?

Do you have the Firefox icon on your quick launch? Close Firefox. Right click on the icon and select Open New Tab. Sometimes this works. If it opens, close it by Menu > File > Exit.

If it's like the fake FBI/Interpol browser lock page, This add-on can stop such pages; disallow Script Button {web link} 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.

no it does not come up when starting browser. it happens while using browser. i will try to get more info when it happens again. think may be something in my email. not sure,use netzero. has never happened with edge or internet explorer. just recently switched to firefox as default brower

Adblock Plus {web link} Blocks annoying video ads on YouTube, Facebook ads, banners and much more. Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).

Adblock Plus Pop-up Addon {web link} Adblock Plus Pop-up Addon extends the blocking functionality of Adblock Plus to those annoying pop-up windows that open on mouse clicks and other user actions.

Forum; Adblock Plus Homepage {web link}

used malware bytes. it removed something from my recycle bin. have not had problem since. thank you