What is in the window? Did the problem just start? Have you tried closing the browser? If it's like the fake FBI/Interpol browser lock page, A way out of a trap page is to (force it if needed) '''Close Firefox. ''' Wait about 20 seconds for Firefox to finish closing. Right-click on the Firefox icon and select '''Open New Window. ''' +++++++++++++++++++++++++++++++++++++++++ Sometimes this works. If it opens, close it by '''Menu > File > Exit. ''' This will flush out that web page from the '''Session Store. '''