I meant to say cannot open it in the first sentence sorry

Note that you can find "Edit this question" under the "Question Tools" menu in the sidebar (you may have to scroll to the top), for a reply, "Edit this post" is in the three-dot menu next to a reply.

Boot the computer in Windows Safe Mode with network support to see if that has effect.

• https://www.bleepingcomputer.com/tuto.../how-to-start-windows-in-safe-mode/
• https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10/

Try to start Firefox in Troubleshoot Mode to see if that works.

• Windows: hold down the Shift key while starting Firefox
• Mac: hold down the Options key while starting Firefox
• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode

didn’t work :/ but thanks for trying to help.

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.

• download the Firefox installer and save the file to the desktop
  *https://www.mozilla.org/en-US/firefox/all/#product-desktop-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 the current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including personal data in profiles created by other Firefox versions

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

• (64-bit Firefox) "C:\Program Files\Mozilla Firefox\"

• it is important to delete the Firefox program folder to remove all the files and make sure there are no problems with files that were leftover after uninstalling

Your personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you 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, you can create a new profile as a quick test to see if your current profile is causing the problem.

• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data
• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Reinstall Firefox

• https://support.mozilla.org/en-US/kb/troubleshoot-and-diagnose-firefox-problems

Your Microsoft account may have parental controls enabled which limits what browsers you can use. Does it work if you rename firefox.exe to something else?

Your Microsoft account may have parental controls enabled which limits what browsers you can use. Does it work if you rename firefox.exe to something else?

yes this worked thanks so much!!!!!!!!!!!!

Note that DRM protected videos will not play with a modified .exe name. You could try to get the browser limitation removed from your Microsoft account or create a new account.