When I click on emails a message pops up "Thunderbird is already running but is not responding.The old Thunderbird process must be closed to open a new window" It give me an option to close thunderbird or cancel. I always click on close thunderbird but the message pops up again when I need to look at my emails. I again click on close thunderbird and it comes up again the next time I want to look at my emails. Can you please help me!!!