Currently no delivery to hello@domain.com (Message no. XS612)

Diagnosis

The message was processed correctly in the SAP system. However, a subsequent system registers that the message cannot currently be delivered to the receiver hello@domain.com.

Information from external system (if available)
SMTP-HOSTNAME:25

452 4.3.1 Insufficient system resources ( UsedDiskSpace [PATH-TO-DISK] )

Procedure

If you send the message again at a later time then it is possible that it can be delivered successfully.

The error ‘452 4.3.1 Insufficient system resources’ means mail server does not have sufficient system storage.

As It indicates that system resource is insufficient on SMTP server, not on SAP side, you have to contact the vendor/administrator of SMTP Server for further help.

Note: The SMTP server is responsible for actually sending the mail out to the recipients. If the SMTP server is low on resources, mails may not be sent.