The RETRYINT statement in hlq.SMTP.CONFIG must contain a positive value. This statement specifies the number of minutes SMTP should wait between attempts to deliver mail to a TCP host that is down. The range of correct values for the RETRYINT statement is 0 and 1440 minutes. SMTP uses the default for the RETRYINT statement, which is 20 minutes. For more information on the RETRYINT statement and hlq.SMTP.CONFIG, see the z/OS Communications Server: IP Configuration Reference