I am a computer dummy! Maybe one the computer experts out there can help me.

I recently tried to set up a new email account in Outlook Express, and I can send mail, but cannot receive any. I changed a bunch of settings in the setup, and then I couldn't send or receive. After screwing around I finally got it to send again but still can't receive any mail. I tried to ask Verizon for help and they said everything appeared to be OK, but I still can't receive...................Anybody got a clue???