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Problems Starting Firefox

  • 7 replies
  • 1 has this problem
  • 27 views
  • Last reply by joe125

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I've been having frequent trouble starting Firefox for the past month or so.

Sometimes I get the Windows error message that Firefox crashed and asks me to restart, check for problems, or debug the application.

Sometimes Firefox will open on a "New Tab" and fail to load my default home page (http://localhost/default.html). A dot on the left side of the tab cycles back and forth continually.

I'm using Windows 7 Home Edition with IIS installed.

Thank you.

All Replies (7)

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Problem signature:

 Problem Event Name:	BEX64
 Application Name:	firefox.exe
 Application Version:	79.0.0.7506
 Application Timestamp:	5f1601d7
 Fault Module Name:	firefox.exe
 Fault Module Version:	79.0.0.7506
 Fault Module Timestamp:	5f1601d7
 Exception Offset:	000000000001293f
 Exception Code:	c0000409
 Exception Data:	0000000000000000
 OS Version:	6.1.7601.2.1.0.768.3
 Locale ID:	1033
 Additional Information 1:	6f6e
 Additional Information 2:	6f6e435dd574b0b2d5ec131f595b0fde
 Additional Information 3:	5fdb
 Additional Information 4:	5fdb74cf3caa422632d470e53148c8c3

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 C:\Windows\system32\en-US\erofflps.txt

Helpful?

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Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.


Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Note: Check Both Folders

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia

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The reinstall process asked to reset defaults and remove add-ons. Since it was checked by default and you didn't mention it, I left it checked.

I'm still having the problem of "Firefox has stopped working."

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Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?


Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

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Firefox reliably starts every time when in Windows Safe mode.

I still cannot get it to reliably start in normal Windows mode.

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In most computers, there are several types of Safe Mode. The primary ones used most are;

  • Safe Mode: Only programs that came with the computer are started. No other programs will be started unless the user starts them.
  • Safe Mode with Networking: Same as above but the network drivers (internet) will also be running.

This is a way to test if one of the other programs on the computer is causing the issue.


As a test, disable your protection programs.

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FredMcD - I appreciate your efforts. I know about the different types of Safe Mode. I am a computer programmer with almost forty years experience.

I will be permanently uninstalling Firefox from my computer.

Thank you for your help.

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