A few days ago, I got multiple copies (like 20) of the same message, with the same time stamp, but over a period of a couple of hours. Now, when I check for new mail, system first shows downloading message 1 of 41, then responds no message to download. I have new messages that haven't been downloaded, but Thunderbird won't download them. I've closed and restarted the program, but still the same result. Even restarted the computer. I'm using gmail with POP3.