Why can't I send or forward emails from my Yahoo account?-Collection of common programming errors

Me too! I can receive and read e-mails but I get an “unknown error” message if I try to send, reply, or forward. Called Best Buy Geek Squad where I bought computer. They couldn’t help me with the e-mail problem, and didn’t have any phone numbers for Yahoo, but suggested I open a second Yahoo account to see if I had the same problem. I did – still couldn’t reply, send, or forward. Therefore the online support is useless. Searched for Yahoo phone numbers. All I found were either no longer in service or a recording directed me to the online web support.