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cannot install firefox because malaware

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  • 1 has this problem
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  • Last reply by cor-el

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cant install firefox doesnt open correctly the setup error message says Run as: you may not have the necessary permissions to use all the features of the program, you may run the program with same or different user, none works, i am the only user of my laptop

cant install firefox doesnt open correctly the setup error message says Run as: you may not have the necessary permissions to use all the features of the program, you may run the program with same or different user, none works, i am the only user of my laptop

All Replies (3)

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First, let's take care of the computer.

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

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.


Download Firefox For All languages And Systems {web link} Save the file. Then;

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder. Linux: Check your user manual.


Look for, and rename any Mozilla or Firefox program folders by adding .old to them.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD folders when you are done.

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What makes you think you have malware ? Please do ensure it is an official version of Firefox so use either mozilla {Fred's link in the post above) or getfirefox.com but not some link you find yourself from a web search.

The Firefox install instructions are here:

If you are certain it is an official version then try right clicking and using run as Administrator. See also (This is actually a Windows 7 potential solution)

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Try to run the Firefox installer or the Firefox program once as Administrator (right-click: Run as Administrator).

Do a clean reinstall of the current Firefox release and delete the Firefox program folder before installing a fresh copy of the current Firefox release.

If possible uninstall your current Firefox version to cleanup the Windows Registry and settings in security software.

  • Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

  • (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

Your personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you uninstall and reinstall or update Firefox, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.

If you keep having problems then create a new profile to test if your current profile is causing the problem.



It is possible that security software (anti-virus, firewall) is causing the problem. Try to disable security software temporarily to see if that makes a difference.