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Mozilla Firefox/Uninvited Incoming file for download


Many times a day at random intervals, I get a gray rectangle offering some 17.4MB file supposedly in .mp4 format from supposedly ~ which interrupts keystrokes if I'm on Firefox, and which I decline by hitting Cancel.

I'm using Windows Firewall on a 64-bit Win7 box, but don't have a clue about stopping this intrusion.  I'm running MS Security Essentials, SpyBot Search & Destroy, and AVG which has proved effective and not much of a load on resources.  One possibly unrelated issue is I periodically get a Windows Explorer has encountered some problem and must be shut down, which I can do by choosing shutdown or seek a Web solution and then restart.  Doesn't matter what I do, some 10-40 hours later it repeats.

Hi Bill,

Sorry about the delay. I keep forgetting to put myself on vacation sometimes.

A grey rectangle? Hm. I'm guessing that it's something malicious. Firefox doesn't usually do that. You might want to scan your computer with all of these tools. Please be sure to use them all as they pick up different kinds of malware/viruses.

Microsoft Security Scanner:
MalwareBytes anti-Malware:
Anti-RootKit Killer - TDSSKiller:
Hitman Pro:
ESET Online Scanner:

You will also want to check to see if some malicious add-ons have been installed without Firefox knowing. Please be sure to check your current add-ons list (Press Ctrl/Cmd (Mac) + Shift + A) and delete any extensions you don't remember installing.

If you are not sure, you can send me your list of add-ons and I'll let you know if everything's okay in that department. You can copy/paste a list of your Troubleshooting Information by going to about:support and pressing the button that says Copy raw data to clipboard then paste it in a new reply to me. No personal information is stored on this data. Mozilla is big on privacy. You can take a look at all your information that's being copied from the about:support page.

Last thing is to uninstall any programs you haven't installed from your computer. You can do this by going to the Control Panel (Start -> Control Panel -> Programs -> Uninstall a Program)

As for your Windows Explorer error, that's most likely not related to Firefox. You should take that error to a Windows forum such as

If you have any questions or need more help, or if you solved this, let me know. :)


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Moses Bermea


I can answer almost any question about Firefox, add-on compatibility, how to force add-ons to work, browsing safely, about:config settings, flash problems. I can read Firefox crash reports and stop ads in Firefox.


I have been volunteering for Mozilla since January 2009 giving me 5 years of experience in both using Firefox, diagnosing problems, and giving correct fixes. I am currently a Moderator over at the Mozilla Support forums.

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