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The application “Firefox” can’t be opened.

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MAC OS 10.11.4

1) when i open firefox - I get this error message - The application “Firefox” can’t be opened.

2) when I try to start firefox in safe-mode same message as above

3) when I try to run /Applications/Firefox.app/Contents/MacOS/firefox-bin -P The error message back /Applications/Firefox.app/Contents/MacOS/firefox-bin: Operation not permitted

4) When I trash can the firefox application and reinstall firefox - get the same error message as step 1

5) when I renamed Policies folder and then start firefox same error message as in item 1 above

6) when I trash can the firefox application with profile folder rename - and install firefox same as item 1

7) when I ran step 3 - the profile manger gui came up - then went away. when I ran step 3 again- I get the error in step 3

Please advise my options - I have bookmarks and security information I need to access - I made a copy of the Profiles folder before I started this process.

thanks, dan

MAC OS 10.11.4 1) when i open firefox - I get this error message - The application “Firefox” can’t be opened. 2) when I try to start firefox in safe-mode same message as above 3) when I try to run /Applications/Firefox.app/Contents/MacOS/firefox-bin -P The error message back /Applications/Firefox.app/Contents/MacOS/firefox-bin: Operation not permitted 4) When I trash can the firefox application and reinstall firefox - get the same error message as step 1 5) when I renamed Policies folder and then start firefox same error message as in item 1 above 6) when I trash can the firefox application with profile folder rename - and install firefox same as item 1 7) when I ran step 3 - the profile manger gui came up - then went away. when I ran step 3 again- I get the error in step 3 Please advise my options - I have bookmarks and security information I need to access - I made a copy of the Profiles folder before I started this process. thanks, dan

All Replies (1)

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Hi Dan, as a Windows user, I am not aware of any secret Mac magic for this problem.

Assuming this began with Firefox 66, I wonder whether you might try installing Firefox 65.0.2 and see whether it can run. It may well want to update right away, but at least we can get a little bit of information this way.

This is the link for the U.S. English version. To choose a different language, please click the .. link (first on the list) and then you will find folders for all the supported locales.

http://archive.mozilla.org/pub/firefox/releases/65.0.2/mac/en-US/