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Installing, firefox, I end up with a panel and a checkbox that blocks everything

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  • 2 have this problem
  • 6 views
  • Last reply by slyestfox

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The download looks like it goes ok, but when it launches firefox, a panel pops up that wants something or is a virus of some kind. It is a 2 by 3 inch rectangle with a bar across it, and has a small square and a questionmark in the middle

The download looks like it goes ok, but when it launches firefox, a panel pops up that wants something or is a virus of some kind. It is a 2 by 3 inch rectangle with a bar across it, and has a small square and a questionmark in the middle

Chosen solution

Many thanks to all. It turned out that McAfee SiteAdvisor had been added to Internet Explorer, and maybe to Firefox as well. When I tried to upgrade Firefox, it was preventing the upgrade and any attempt to reinstall it or load Google Chrome. Apparently it is a lot more restrictive than McAfee itself. Once that was disabled, everything worked fine.

Thanks to all.

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You may have security software blocking the install or the change of your default browser. Also is it genuine Firefox from Mozilla or some dodgy site ? Use getfirefox.com or https://www.mozilla.org/en-US/firefox/all/ and see the help article

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The site was the original Mozilla Firefox. I have McAfee as an antivirus. And also have Internet Explorer.

I had the same issue trying to download Chrome, but now McAfee warns against using that download. I had the same warning when I first tried to download Firefox, but I told it to download anyway, and now I can't use either.

Explorer still seems ok...

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I have to leave for today. Thanks for the help so far. Be back tomorrow.

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In case one of your extensions is involved, could you test the page in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

If Firefox is not running: Hold down the Shift key when launching Firefox.

If Firefox is running and you can access the menu: Either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

and give Firefox the OK to restart.

Both Scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any difference?

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Can you attach a screenshot?

  • Use a compressed image type like PNG or JPG to save the screenshot
  • Make sure that you do not exceed the maximum size of 1 MB
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to jscher2000

firefox looks ok in safe mode. how do I fix the root problem??

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to cor-el

Here's the screenshot of the box that appears. It shows up in front of the firefox screen and is about 2 inch by 3 inch. I've tried clicking on the check box and the question mark, but nothing happens. I then have to close firefox using the task manager

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You can try to disable hardware acceleration in Firefox.

  • Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

You need to close and restart Firefox after toggling this setting.

If it works in Safe Mode and in normal mode with all extensions (Firefox/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via "Firefox > Exit" (Windows: Firefox/File > Exit; Mac: Firefox > Quit Firefox; Linux: Firefox/File > Quit)

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Chosen Solution

Many thanks to all. It turned out that McAfee SiteAdvisor had been added to Internet Explorer, and maybe to Firefox as well. When I tried to upgrade Firefox, it was preventing the upgrade and any attempt to reinstall it or load Google Chrome. Apparently it is a lot more restrictive than McAfee itself. Once that was disabled, everything worked fine.

Thanks to all.