Problem: Because I did not use Google Toolbar (it was automatically installed when I installed Firefox), I decided to uninstall it. I selected the Uninstall option in Tools -> Add-ons -> Google Toolbar in Firefox (Disable option being grayed) and it said that the toolbar will be uninstalled the next time Firefox will restart. So I closed and started Firefox again and I got a popop window that said something like thanks for installing Google Toolbar and if I want to see the page rank for every site I visit etc. This window kept appearing until I agreed installing Google Toolbar. I also tried uninstalling the toolbar using its uninstall setting, but I kept getting the same (reversed) result.
Everytime I closed the Firefox browser window I got sure that the procees was closed (no instances of FF remained opened).
My operating system is Windows XP Professional.
The solution that worked for me consists of two simple steps:
1. I uninstalled Google Toolbar for Internet Explorer using Control Panel -> Add/Remove programs.
2. I pressed Disable (not grayed anymore) and then Uninstall buttons for Google Toolbar in Firefox Tools -> Add-ons and restarted Firefox.
And it worked! No annoying popop window anymore.