After installing SugarCRM email ids have to be configured for sending and receiving emails. Which can be a painful task if you don’t know the SMTP and POP3 servers of your host.
All the hosts provide the SMTP and pop3 server configurations which can be used to configure the email ids in the SugarCRM. I installed SugarCRM on 1and1.com shared hosting; there pop3 server works perfectly fine but for sending out the emails the SMTP server doesn’t work for some reason. Sendmail option can be used instead of SMTP but when you send emails using sendmail are marked as spam.
After researching for the problem I found out the solution. IP address of the SMTP server (74.208.5.2) must be used that means put 74.208.5.2 instead of smtp.1and1.com in the SMTP server configuration and it will work fine.