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Downloaded the 11.0 version of Mozilla Firefox to replace old version 9.0. After installation, and on the first launch attempt, received a message: "MOZCRT.dll missing" I researched, tried the prescribed remedy below, to no avail. Please advise.

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  • آخر ردّ كتبه cor-el

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Here is the unsuccessful solution I attempted (3 times):


Download a fresh Firefox copy and save the file to the desktop. Firefox 11.0.x: http://www.mozilla.com/en-US/firefox/all.html

Uninstall your current Firefox version, if possible. Do NOT remove personal data when you uninstall the current version or you lose your bookmarks and other data in the profile folder.

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

Here is the unsuccessful solution I attempted (3 times): Download a fresh Firefox copy and save the file to the desktop. Firefox 11.0.x: http://www.mozilla.com/en-US/firefox/all.html Uninstall your current Firefox version, if possible. Do NOT remove personal data when you uninstall the current version or you lose your bookmarks and other data in the profile folder. Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

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

If you use ZoneAlarm Extreme Security then disable Virtualization and reinstall Firefox.
Other security software may have similar features to prevent Firefox from updating files properly.

See these pages for a similar issue with corrupted files: