Roadrunner/RR Mail is a type of webmail service that allows users to send and receive messages over the internet. It also provides a way for users to communicate with one another without having to pay any cost for email services or a dedicated internet connection. SMTP server uses the SMTP protocol to send emails. And only to send, because other protocols are used for receiving POP3 and IMAP. The data transfer is done via TCP connection, and the specification of Simple Mail Transfer Protocol is optimal for sending mass and transactional mailings. In case the error still persists, contact customer support team. A team of skilled and well qualified professionals will assist you resolving the issue of Roadrunner SMTP Server not working issue. Roadrunner experts, who are recognized for analyzing the customer’s queries, seize quickly and endow with solutions even quicker.