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Can't open Firefox

  • 4 replies
  • 1 has this problem
  • 17 views
  • Last reply by cor-el

rcitti1
rcitti1
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This morning, when I tried to open Firefox I got a message saying that Windows couldn't locate the file.

I originally just clicked on the icon on my screen.

I then tried going to the program file folder and opening by clicking on the exe file. Same message.

I tried downloading a new copy of Firefox.

The same message came up when I tried to open it.

I made Firefox an exception on my security software. No change.

Any ideas what to do next?

This morning, when I tried to open Firefox I got a message saying that Windows couldn't locate the file. I originally just clicked on the icon on my screen. I then tried going to the program file folder and opening by clicking on the exe file. Same message. I tried downloading a new copy of Firefox. The same message came up when I tried to open it. I made Firefox an exception on my security software. No change. Any ideas what to do next?

Chosen solution

See https://support.mozilla.org/en-US/questions/1290655 Windows can't find Firefox-follow up

It looks like this is now resolved.

Read this answer in context 👍 0

All Replies (4)

AliceWyman
AliceWyman
  • Moderator
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Chosen Solution

See https://support.mozilla.org/en-US/questions/1290655 Windows can't find Firefox-follow up

It looks like this is now resolved.

Himanshu prabhakar
Himanshu prabhakar
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The Refresh Firefox feature can fix many issues by restoring Firefox to its default state while saving your essential information. Consider using it before going through a lengthy troubleshooting process. The Firefox Safe Mode window includes a Refresh Firefox option. You can start Firefox in Safe Mode by holding down the shift key while starting Firefox.

There is some links which also helps after that above https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode#w_safe-mode-window

Thanks

Modified by Himanshu prabhakar

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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Hi rcitti1, if I understand your solution correctly, you did this:

  1. Open the Firefox program folder: C:\Program Files\Mozilla Firefox
  2. right-click the file firefox.exe and choose Copy
  3. right-click a blank area of the folder and choose Paste -- Windows creates a file named firefox - Copy.exe
  4. Double-click firefox - Copy.exe to launch Firefox successfully.

Wow, that's strange.

Over the years, some malware that prevented Firefox from running was fooled by adding a 1 to the file name, i.e., firefox1.exe. While I don't know whether you have malware on your system, it's worth doing some follow-on scans, I think. Our support article recommends some tools for that: Troubleshoot Firefox issues caused by malware.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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This is a problem with Avast making changes to some registry keys.

  1. Open run (Windows key + r)
  2. Type: regedit
  3. Navigate/Search to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Option
  4. Delete the (Debugger) folders of the apps that do not work