This post related to Oracle Applications Server level Setups related to Dunning letters.
Assumption: It is assumed that the Dunning letter process is not customized.
below steps applies for standard process.
1. Ensure the profile has correct smtp server name "IEX: SMTP host",if not enter the correct smtp server name and save it.
2. Enter the valid email address through which the dunning letters need to be sent "IEX:SMTP from".
3. Configuring XDO : xdodelivery.cfg
3.1 Login to Oracle Applications concurrent manager server, cd $XDO_TOP
3.2 check resource folder exists , if not create resource folder
3.3 if resource exists , check xdodelivery.cfg exists or not, if not create xdodelivery.cfg.
3.4 Add the below entry in xdodelivey.cfg. in the host tag, ensure correct smtp hostname, in port tag ensure correct smtp port (which generally 25)