Hi,

I am using Mozilla Thunderbird 1.5. It has been working fine until
today. I can receive e-mails but when I send an e-mail, I receive a
message that says "An error occurred while sending mail. The mail
server responded: sender requires authentication. Please verify your
email address is correct in your Mail preferences and try again."

I have checked the mail preferences and they look correct. Is there
something that I have done wrong or somewhere else that I need to
check.

Thanks,
LS