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Use this customizing to not allow sending attachments bigger than the specified size (in bytes) from SAP ECC/S4 to SAP FSM. If no value is entered, the value of 5242880 bytes (5.24 MB) will be used.
// the conversion thing and that MB setting must be bigger than FSM
// the transporter thing
// the attachment resending thing and how it’s affected by CUST_ATTA max att. size
// example recommended values