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crashing firefox

  • 4 replies
  • 2 have this problem
  • 4 views
  • Last reply by Fordster

Fordster
Fordster
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Firefox had one of those annoying pop up boxes for an updated version and I clicked ok as always, but now when I launch Firefox, I get an error - The exception unknown software exception (0xc0000409) occurred in the application at location 0xe49f47cf. Click on OK to terminate the program. Please help

Firefox had one of those annoying pop up boxes for an updated version and I clicked ok as always, but now when I launch Firefox, I get an error - The exception unknown software exception (0xc0000409) occurred in the application at location 0xe49f47cf. Click on OK to terminate the program. Please help

All Replies (4)

Paul
Paul
  • Top 25 Contributor
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Hi

From what you are describing, you may have downloaded some malware. That does not sound like it was a valid or legitimate Firefox update and we are aware of some malicious updates that act in the manner that you describe. What you were seeing was not something produced by Mozilla (the people that make Firefox).

If you are able to, I would recommend immediately:

  1. Backing up your bookmarks and passwords. This article will help, but I recommend you capture just the bookmarks and passwords. By capturing the full profile you may drag over elements of the malware.
  2. Remove Firefox from your device. This article will help.
  3. Running full anti-malware scans of your device using the software that you have installed.
  4. Install Firefox from https://www.mozilla.org/en-US/firefox/new/.

For more information about reducing the impact of malware, I recommend having a read of this article and also this which will explain how a legitimate update will take place.

I hope that this helps, but if not, please come back here and we will do our best to help.

Fordster
Fordster Question owner
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Hi thanks for the quick response. Does that mean there was no official update in the last 24-48hrs? I think I am on the betas as well, but I can't see as I keep getting the error. The update dialog box was the same as it always is, so if its malware then it looks like Mozilla will need to update the way they notify updates. I will try what you babe suggested, but I honestly believe that this is a bug with the update rather than malware. I will update when I can get a fresh copy of firefox Cheers

Paul
Paul
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Hi

Might be worth checking that...

Please can you type about:support into the address bar and copy the Build ID and the Version into a reply to this thread.

This will allow us to see which version you are on and when it last updated.

Fordster
Fordster Question owner
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Hi. I have it fixed, I dont know how, but windows needed updating too so I installed and restarted (again) and now it seems to be working. I checked the build and it is 57.0b7 (64-bit) and that update was installed Oct. 11th 2017 12:38:21pm.

So thanks for your help. On a side note, I dont have another browser installed on my pc, and was trying to download a fresh install of Firefox with my windows phone(its awful, I know) but your link only took me to the Android version, and I could not get to desktop version anywhere, that's just for future reference.

So thanks again Cheers