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Firefox failed automatic update repeatedly. Finally decided to uninstall and do a clean reinstall. Install download opens and then closes and goes no further. Downloaded the install file from IE and tried again. Same result. Decided to try Safari. Same pattern. Install file opens the closes and no further action accept Safari popup message says "Missing DLL", But it doesn't say which DLL. I have no idea how to fix this. Miss my Firefox. Help!

Firefox failed automatic update repeatedly. Finally decided to uninstall and do a clean reinstall. Install download opens and then closes and goes no further. Downloaded the install file from IE and tried again. Same result. Decided to try Safari. Same pattern. Install file opens the closes and no further action accept Safari popup message says "Missing DLL", But it doesn't say which DLL. I have no idea how to fix this. Miss my Firefox. Help!

Chosen solution

Such problems can be caused by security software.

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.

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

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

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will lose all 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.

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

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.


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Seçilmiş Həll

Such problems can be caused by security software.

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.

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

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

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will lose all 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.

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

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.


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problem solved. Thank you.