Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Do a malware check with some malware scanning programs on the Windows computer.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.

• http://www.malwarebytes.org/mbam.php - Malwarebytes' Anti-Malware
• http://www.superantispyware.com/ - SuperAntispyware
• http://www.microsoft.com/security/scanner/en-us/default.aspx - Microsoft Safety Scanner
• http://www.microsoft.com/windows/products/winfamily/defender/default.mspx - Windows Defender: Home Page
• http://www.safer-networking.org/en/index.html - Spybot Search & Destroy

You can also do a check for a rootkit infection with TDSSKiller.

• http://support.kaspersky.com/viruses/solutions?qid=208280684

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked

FIrefo does work after booting in windows safemode. I do not have any profies. It simply will not start up in normal windows boot mode. I have tired all the scan etc...uninstalled..reinstalled... wiped all firefox profiles..etc...

If it works when you boot the computer in safe mode then it is possible that your security software is causing this problem.

Which security software (firewall, anti-virus) do you have?

I am running avast. I will run a series of experiments to see if that is the problem. I now have spybot, super anti spy ware and malwarebytes running. It is not likely any of those since i installed to after firefox stopped working in an attempt to resolve the problem.

I have tried to disable Avast with no luck. I even uninstalled the mozilla browser protection plugin specific to Avast and still no luck. My next step will be to completely uninstall avast to completely rule it out and delete all its' local data. Any other suggestions would be appreciated. Keep in mind that Internet and Explorer and Chrome work.

I installed the X64 version and I am up and running, Somehow at 32bit file that window provides is corrupt. Does anyone know what file/s these might be?