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Firefox not launching after update - since version 146 - Requires reinstall after each update

  • 3 replies
  • 0 have this problem
  • 2 views
  • Last reply by TyDraniu

super_118
super_118

In my org - ever since the release of Firefox 146 - each time an update is rolled out on a WIndows 11 endpoint - Firefox is no longer able to launch.

This is resolved by uninstalling and reinstalling the client. We've had no issues with the ESR release in my testing.

What changed? Anyone else experiencing this?

I had our security team take a look at the antivirus - they've confirmed we aren't blocking Firefox and they did not see any block reports.

No relevant policy changes have gone through around the time of the incident. Initially I suspected users were installing Firefox ESR from the Company Portal alongside the standard release - but confirmed this is not the case. Also ruled out browser extensions - error persisted across a config without any extensions.

Please let me know if there is troubleshooting info I can collect. I included info from my own browser, but I reinstalled on the 27th and it has been working since. However, it has broke specifically on the days new releases have come out.

Thank you for any suggestions!

In my org - ever since the release of Firefox 146 - each time an update is rolled out on a WIndows 11 endpoint - Firefox is no longer able to launch. This is resolved by uninstalling and reinstalling the client. We've had no issues with the ESR release in my testing. What changed? Anyone else experiencing this? I had our security team take a look at the antivirus - they've confirmed we aren't blocking Firefox and they did not see any block reports. No relevant policy changes have gone through around the time of the incident. Initially I suspected users were installing Firefox ESR from the Company Portal alongside the standard release - but confirmed this is not the case. Also ruled out browser extensions - error persisted across a config without any extensions. Please let me know if there is troubleshooting info I can collect. I included info from my own browser, but I reinstalled on the 27th and it has been working since. However, it has broke specifically on the days new releases have come out. Thank you for any suggestions!

All Replies (3)

TyDraniu
TyDraniu
  • Top 10 Contributor

Do you use SentinelOne software in your organization?

super_118
super_118 Question owner

Hi!

Yes, we do use SentinelOne. Has this been a known issue?

The affected endpoints share a common error - Firefox is trying to access a location in memory that gets denied. There was also a case where a scheduled task from Firefox Default Browser Agent was blocked - but this only occurred once.

This error occurs each time:

Faulting application name: firefox.exe, version: 147.0.1.271, time stamp: 0x696a121b Faulting module name: unknown, version: 0.0.0.0, time stamp: 0x00000000 Exception code: 0xc0000005 Fault offset: 0x00007fffa9a26160 Faulting process id: 0x0x80C Faulting application start time: 0x0x1DC9576088DD2AC Faulting application path: C:\Program Files\Mozilla Firefox\firefox.exe Faulting module path: unknown Report Id: 70a861e5-befc-4833-9eb4-617a5c860ea6 Faulting package full name: Faulting package-relative application ID:

Thank you for any and all assistance.

TyDraniu
TyDraniu
  • Top 10 Contributor

It's been a known issue in 146, I'm sure it should be working in 147.0.3. It may be something else, but try to disable the Sentinel client for confirmation.

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