Disregard. I was able to Force Quit Firefox. I still have problems with scripts not responding. I have to click closed 4-5 windows before I can do anything.

What are you doing when the error comes up? What page were you on?

That screenshot is of a Warning: Unresponsive Script for the about:blank internal page - a "page" that has no content, it is "blank". You might want to consider troubleshooting your add-ons.

https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Thanks, I will try that.

UPDATE: Saturday 16 May 2015

Same problems as below now exist on THREE machines -- one Windows 7 64bit desktop, and two laptops Windows 7 64bit, all Win 7 SP1, updated with latest MS Updates.

Updated to Firefox 38.0.1 Windows 7 64bit...previous version of FF was working fine and was meticulously crafted by experienced tech user.

Now, we have two major troubles immediately happened with update to 38.0.1:

1. Will NOT close Firefox (have to use Task manager). Nothing we do within FF closes it 2. Firefox will NOT open New Private Window, only after we located a New Private Window toolbar icon will item #2 work.

Again, this is the fifth straight time after Updating FF that it suddenly creates new and not-seen-before problems.

This is NOT due to Add-Ons, it's not due to Plug-In's... it's due to a sudden new problem(s) introduced by the Updated FF 38.0.1, now on three different machines.

Starting FF in Safe Mode is tacitly useless and time-consuming, and proves nothing, allows nothing to be checked or changed, the problems remain.

When having to use Task Manager to close FF 38.0.1, restarting FF again calls in the Crashed Session Manager and we have to recover from what FF insists is a crashed session.

Why oh why are these new problems suddenly introduced each time we users update ?

Now what's been changed or altered, all without our knowledge, and not mention in ANY of the new FF notes, etc.

EVERY time we update, it's essentially introducing inferior performance and problems in an otherwise finely tuned previously working FF.

Joe

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Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

• 1 Download Firefox Full Installer For All languages And Systems {web link}
• 2 Uninstall Firefox from your computer {web link}
  DO NOT remove your profiles.
• 3 After, reboot the computer. Then run the full installer.

Last Resort: https://support.mozilla.org/en-US/kb/install-older-version-of-firefox