I opened an account with Gmail some months ago to use their POP3 service to collate my various Yahoo and Hotmail accounts in one place. All of a sudden, about two weeks ago, I find that I am unable to send from my Yahoo email address even though they were previously working on Gmail and all are well used friends and family email addresses. The problem happens in specific combinations, that is, sending from my Yahoo account to someone else's Yahoo account via Gmail and also it didn't work when I sent from my Yahoo, via Gmail, to my Hotmail, which I have registered to Gmail POP3. Both got bounced back. How do I circumvent this problem and resume normal service. Thanks, Tom.