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Firefox 56/57 for Mac crashes on startup - every time. (Despite clean reinstall)

  • 5 replies
  • 4 have this problem
  • 2 views
  • Last reply by BTony

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Hi all,

I rely heavily on FireFox (primarily for the multiple profiles and extensions it provides), so deperately trying to solve a problem I'm having. When I launch Firefox on my Mac (10.12.6 - Sierra), I immediately receive an error: "Firefox quit unexpectedly."

I've tried a number of different approaches to resolve including:

1) Starting Firefox in safe mode (by holding down the opt key on launch) - same error occurs 2) Removing Firefox from the Applications folder, and removing Firefox folder from the Application Support folder under the Library (which also removes all my profiles). Then reinstalled Firefox 57. - same error occurs 3) Tried installing older version of Firefox - version 56.0.2 (after removing previous installation as per step 2 above) - same error occurs 4) Tried a machine restart (very early on) - same error occurs.

I've run out of ideas, and hoping someone may be able to shed some light or suggest further troubleshooting options? Desperate to get it working again!

Cheers, Mark

The detailed error report (or at least the start of it) is here:

Process: firefox [1511] Path: /Applications/Firefox.app/Contents/MacOS/firefox Identifier: org.mozilla.firefox Version: 56.0.2 (5617.10.24) Code Type: X86-64 (Native) Parent Process:  ??? [1] Responsible: firefox [1511] User ID: 1342407268

Date/Time: 2018-01-08 14:25:11.798 +1100 OS Version: Mac OS X 10.12.6 (16G1114) Report Version: 12 Anonymous UUID: C6B6E4AB-1DE7-8875-3841-965087F69AAD


Time Awake Since Boot: 820 seconds

System Integrity Protection: enabled

Crashed Thread: 1

Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x0000000106f5bc92 Exception Note: EXC_CORPSE_NOTIFY

Termination Signal: Segmentation fault: 11 Termination Reason: Namespace SIGNAL, Code 0xb Terminating Process: exc handler [0]

Hi all, I rely heavily on FireFox (primarily for the multiple profiles and extensions it provides), so deperately trying to solve a problem I'm having. When I launch Firefox on my Mac (10.12.6 - Sierra), I immediately receive an error: "Firefox quit unexpectedly." I've tried a number of different approaches to resolve including: 1) Starting Firefox in safe mode (by holding down the opt key on launch) - same error occurs 2) Removing Firefox from the Applications folder, and removing Firefox folder from the Application Support folder under the Library (which also removes all my profiles). Then reinstalled Firefox 57. - same error occurs 3) Tried installing older version of Firefox - version 56.0.2 (after removing previous installation as per step 2 above) - same error occurs 4) Tried a machine restart (very early on) - same error occurs. I've run out of ideas, and hoping someone may be able to shed some light or suggest further troubleshooting options? Desperate to get it working again! Cheers, Mark The detailed error report (or at least the start of it) is here: Process: firefox [1511] Path: /Applications/Firefox.app/Contents/MacOS/firefox Identifier: org.mozilla.firefox Version: 56.0.2 (5617.10.24) Code Type: X86-64 (Native) Parent Process: ??? [1] Responsible: firefox [1511] User ID: 1342407268 Date/Time: 2018-01-08 14:25:11.798 +1100 OS Version: Mac OS X 10.12.6 (16G1114) Report Version: 12 Anonymous UUID: C6B6E4AB-1DE7-8875-3841-965087F69AAD Time Awake Since Boot: 820 seconds System Integrity Protection: enabled Crashed Thread: 1 Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x0000000106f5bc92 Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Segmentation fault: 11 Termination Reason: Namespace SIGNAL, Code 0xb Terminating Process: exc handler [0]

Chosen solution

Hi Fred,

Thanks for the quick response. Since posting the message, I managed to find a resolution. It seems there are a number of machines in our organization that were impacted by a recent Apple security patch. Unfortunately I don't have the specifics.

Anyway, downloading and applying the following Apple update manually fixed the issue: https://support.apple.com/kb/DL1940?locale=en_US

Cheers, Mark

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All Replies (5)

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Try installing the ESR version. Do you have the same problem?

Firefox; Extended Support Release {web link} ESR Notes System Requirements

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Chosen Solution

Hi Fred,

Thanks for the quick response. Since posting the message, I managed to find a resolution. It seems there are a number of machines in our organization that were impacted by a recent Apple security patch. Unfortunately I don't have the specifics.

Anyway, downloading and applying the following Apple update manually fixed the issue: https://support.apple.com/kb/DL1940?locale=en_US

Cheers, Mark

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That was very good work. Well done.

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I have the same problem. macOS Sierra 10.12.6 Stopped working immediately after a security update.

Just tried the ESR and get the same crash.

Also, unable to install Security Update 2017-002 as it complains that my OS does not meet the requirements!

I have no working Firefox browser. Any suggestions?

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Update on my situation. Security Update 2018-001 was pushed out to my machine (by my company) today and after the update & reboot, Firefox began working fine.