I have been able to send e-mail before and have not changed any e-mail settings.
I am able to receive e-mails and am using authenticated SMTPs. However when I try to send mail it gives me a "Cannot connect to server message".
Possibly your ISP has begun blocking the port your seding E-mail though. Try switching to outgoing server port 587.
Yeah I'm pretty sure that's it, thanks. I've never run into that problem before, but I took my laptop to someone's office with SBC Yahoo! DSL and I couldn't send any e-mails.