Thunderbird freezes doesn't respond when I do anything like click on something or even move the mouse. It works fine for the first few seconds after it starts but immediately slows down and constantly freezes. I have restarted in safe mode and this seems to make the problem go away. I am using McAfee anti virus, and have disabled it in the add-on menu, but I am having the same problem. I just started having the problem this week. Thunderbird also now uses about 30% of my cpu when it is running. I have an I7 processor with 8 gigs of memory.