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firefox will not open

when i tried to open firefox today, it said that it could not find c:/program files/mozilla firefox/firefox.exe. when i go to the file location it is there, but is listed as a .sig file? is that right? i have tried registry editor, uninstalling and reinstalling, etc. i have not done windows update 1909 because i did it before and things went all wonky so i went back to 1809. i don't know if that could have anything to do with it? is there a difference between just downloading firefox and i keep seeing "full version"...i am very confused. and fairly tech savvy. help, please. thank you.

when i tried to open firefox today, it said that it could not find c:/program files/mozilla firefox/firefox.exe. when i go to the file location it is there, but is listed as a .sig file? is that right? i have tried registry editor, uninstalling and reinstalling, etc. i have not done windows update 1909 because i did it before and things went all wonky so i went back to 1809. i don't know if that could have anything to do with it? is there a difference between just downloading firefox and i keep seeing "full version"...i am very confused. and fairly tech savvy. help, please. thank you.

தீர்வு தேர்ந்தெடுக்கப்பட்டது

Hi Eyelurk, do you use Avast by any chance? Several Avast users are reporting similar problems today, as well as some that might or might not run Avast.

One possible workaround is to move Firefox to a different folder. This may help, but unfortunately I cannot tell you what is going on on your system.

Other Threads

Program Move Workaround

The user in that third thread reported that moving the contents of:

C:\Program Files\Mozilla Firefox

to

C:\Program Files (x86)\Mozilla Firefox

allowed Firefox to run. The user in the second thread reported that worked for them. I don't know why that would make a difference.

Read this answer in context 👍 1

All Replies (5)

தீர்வு தேர்ந்தெடுக்கப்பட்டது

Hi Eyelurk, do you use Avast by any chance? Several Avast users are reporting similar problems today, as well as some that might or might not run Avast.

One possible workaround is to move Firefox to a different folder. This may help, but unfortunately I cannot tell you what is going on on your system.

Other Threads

Program Move Workaround

The user in that third thread reported that moving the contents of:

C:\Program Files\Mozilla Firefox

to

C:\Program Files (x86)\Mozilla Firefox

allowed Firefox to run. The user in the second thread reported that worked for them. I don't know why that would make a difference.

@jscher2000 thank you so much. this solved the problem of firefox not opening. it did a couple quirky things like turned the firefox icon into a text document icon, but that was fairly easily fixed. i just had to change to file location in properties. one thing i noticed was that mozilla maintenance service was always in the c:program files (x86) folder. so maybe that's the weirdness that allows this solution to work. i don't know, but thanks again. and i also appreciate how quickly you responded. hope this helps other people who are tearing their hair out over this.

Eyelurk மூலமாக திருத்தப்பட்டது

There's some discussion in the following thread of registry changes made by Avast Cleanup that could be rolled back as a more general solution. I don't have Avast so I haven't had eyes on the issue from that perspective:

https://support.mozilla.org/questions/1290490

  1. open run (Windows key + r)
  2. type regedit
  3. navigate to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Option
  4. delete the folders of the apps that don`t work (or search for the Debugger key)

Avast has issued an update for Avast Cleanup that should fix this for Avast users: https://forum.avast.com/index.php?topic=234798.0