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How to download firefox on windows 8.1 64 bit?

  • 3 replies
  • 1 has this problem
  • 30 views
  • Last reply by NCP13

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After the firefox installer downloaded and I ran the program a "Run As" window opens (see attached picture). I have tried running it under current user, however after I hit okay nothing happens. I have also tried running it under administrator, but I do not know the correct password.

After the firefox installer downloaded and I ran the program a "Run As" window opens (see attached picture). I have tried running it under current user, however after I hit okay nothing happens. I have also tried running it under administrator, but I do not know the correct password.

All Replies (3)

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I guess the picture did not attach so here it is again

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Check that Firefox isn't set to run as Administrator. Right-click the Firefox desktop shortcut and choose "Properties". Make sure that all items are deselected in the "Compatibility" tab of the Properties window.

  • Privilege Level: "Run this program as Administrator" should not be selected
  • "Run this program in compatibility mode for:" should not be selected

Also check the Properties of the firefox.exe program in the Firefox program folder (C:\Program Files\Mozilla Firefox\). If you can't make changes then start Windows Explorer as Administrator.


It is possible that your security software (firewall, anti-virus) blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access to install for Firefox and the plugin-container process and the updater process.

See:

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I honestly don't know what half of what you said means. However, I can tell you nothing under the compatibility tab in the firefox program was checked and I do not have a firefox desktop shortcut.