When I opened Thunderbird today it downloaded messages but I could not see the messages because the screen was stuck on a date earlier in august. I tried to scroll to the top of the screen to see the incoming messages, but that didn't work. I also could not close the program, it was not responding to the cursor. Then I tried to force close it with ctrl-alt-delete and I could not fix the cursor on the line 'Thunderbird'. This line was constantly shifting. I closed all the other programs and shut down the computer. When I turned the computer on a few hours later, Thunderbird refuses to open. All other programs open normally. Could it be a virus? Also, when I tried to do a threat scan with Mc Afee, I did not receive the normal window but something about a folder and 'nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn' as if it was filling out itself. Please help.