The following settings can be used with the SMTP/400 V1.34 or above to debug problems when sending email. Once these settings are enabled, the mail commands will create a spool file named RJSSMTPLOG after each report is sent. The log will contain the entire SMTP mail session. You can check the log for errors.
Sign on to the AS/400 and run the following commands
SMTPDEBUG OPTION(*SET) DEBUGOPT(*YES)
SMTPDBGPRT OPTION(*SET) DEBUGOPT(*YES)
Once these commands have been run you can manually or automatically attempt to email a report and the log report spool file should be generated. Work with RJS Software Systems to analyze the error log if you need assistance interpreting the SMTP session log.