Strange firefox bug

Solution 1:

I think the interesting part of this error is that he's typing in a web address and Firefox is prepending

file:///C:/Program Files/Mozilla Firefox/chrome/en-US.jar!/locale/browser-region/region.properties

to the address. If the above solutions don't fix the issue I would completely remove FF, delete the folder under Program Files to be sure and reinstall.

Solution 2:

Try disabling all of your add-ons. (Like the Ask toolbar.) Then restart the browser and see if the problem still exists. I've noticed sometimes that firefox won't load a web page for me, but when I disable the StumbleUpon toolbar, it works just fine.

Solution 3:

This thread suggests the problem might be with Ask.com toolbar add-on which apparently can come when you install the COMODO firewall

Solution 4:

Do you have the Ask toolbar installed?
If so, retry after removing it.

In some cases, you may also need to reset preference settings related to the toolbar after disabling or uninstalling it.

In particular, toolbars that include an Internet search feature (such as the Ask.com Toolbar) change the default search provider by modifying the Keyword.URL preference.