SMTP - Outgoing mail fails

I installed eM Client 3 -Windows 7. I can receive mail fine. I’m unable to send mail. I get the response:” SMTP server doesn’t support authentication”. If I uncheck the box under the SMTP tab labeled “Server requires authentication”, mail can be sent. I don’t want to send mail without authentication, right? How do I get around this? My ISP is Road Runner.

Hello,
it depends on your ISP. If your ISP doesn’t support authentication you won’t get around that.
This authentication isn’t very important for your personal safety. It’s more for your provider’s protection.

So how do we shut off the error messages from popping up all the time?