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My computer won't allow download, says Firefox download has a virus.

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  • 4 have this problem
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  • Last reply by Dena227

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My "smart screen filter" says the Firefox 44.0.1 has a virus and won't download it. Also, I can't download the "troubleshooting information" aid. I don't know how to open/save that type of file - xpi.

My "smart screen filter" says the Firefox 44.0.1 has a virus and won't download it. Also, I can't download the "troubleshooting information" aid. I don't know how to open/save that type of file - xpi.

Chosen solution

The smartscreen in Edge can be turned off in settings, and then the otherwise blocked file may then be downloaded. It is possible it is expecting the 44.0.2 that is coming as current version.

Also some antivirus or protection software things on Windows can still have a issue with the stub installer and not the full offline setup. The stub has existed since Firefox 18.0.

You could try the full setup from www.mozilla.org/firefox/all/


edit: Firefox 44.0.2 is now out as it was not listed on www.mozilla.org/firefox/all/ earlier.

https://www.mozilla.org/firefox/44.0.2/releasenotes/

Read this answer in context 👍 1

All Replies (6)

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Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

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/XP if you don't already have one. Windows 8 has antivirus built-in already.

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

Did this fix your problems? Please report back to us!


In regards to your issue with installing the troubleshooting information aid, I assume that your are refering to the SUMO Troubleshooter addon. If that is the case, you can install it quickly and easily from here.

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Can NOT open the SUMO troubleshooter...still! The Microsoft safety scanner found nothing. Now what?

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BTW, I have windows 10

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Chosen Solution

The smartscreen in Edge can be turned off in settings, and then the otherwise blocked file may then be downloaded. It is possible it is expecting the 44.0.2 that is coming as current version.

Also some antivirus or protection software things on Windows can still have a issue with the stub installer and not the full offline setup. The stub has existed since Firefox 18.0.

You could try the full setup from www.mozilla.org/firefox/all/


edit: Firefox 44.0.2 is now out as it was not listed on www.mozilla.org/firefox/all/ earlier.

https://www.mozilla.org/firefox/44.0.2/releasenotes/

Modified by James

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Hi Dena227, another user reported a problem with SmartScreen yesterday. Can you confirm that the "full" (also known as "offline") installer from James' link could be downloaded and run without complaint?

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jscher2000 - Yes, it worked fine using the "full" installer James provided.