One of my clients is running PAP4 on a windows box with shared hosting from Go Daddy. For some reason, he is unable to use the PHP mail() function from within PAP4 despite his Joomla CMS working just fine with that setting in the Global Settings (Too bad PAP4 doesn’t just use the globals), so we were able to set the SMTP settings for relay email instead:
user: name without @domain.com
password: email password
*no smtp authentication
Note: don’t forget to check your relay limits under your email setup. You may have to purchase more if you do more than 25 relays per day.