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my firefox has an issue of incompatible application how do i fix it so it will work again?

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  • 16 have this problem
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  • Last reply by cor-el

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so i guess because of this promblem it won't open up i tryed to install it again and unistall i but it won't work because it say's it was running in te background when i know it was not i also try troubleshooting the program and it won't fix my issue it says that it is incompatible application andit says check for online support so i ask you guys for ou'r help thanksfor you'r coraparation from:, a user of firefox

so i guess because of this promblem it won't open up i tryed to install it again and unistall i but it won't work because it say's it was running in te background when i know it was not i also try troubleshooting the program and it won't fix my issue it says that it is incompatible application andit says check for online support so i ask you guys for ou'r help thanksfor you'r coraparation from:, a user of firefox

All Replies (2)

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Could you post the specific error message you got?

Sometimes when you close Firefox it does not unload completely from memory; then you get the message that Firefox is still running. This article has some potential solutions for this problem: https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding#w_firefox-hangs-when-you-quit-it

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Which security software (firewall, anti-virus) do you have? Did you check your security software (firewall)?


Do a clean (re)install and delete the Firefox program folder (C:\Program Files\Mozilla Firefox\).

Download a fresh Firefox copy and save the file to the desktop.

Uninstall your current Firefox version, if possible.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

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

Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.