3737529 - Error Message "552 5.3.4 Error: Message File Too Big"

Email output fails during transfer to the SMTP server; the message is not delivered to the recipient.

It fails with below error message

SMTP response: "552 5.3.4 Error: message file too big".

SAP Business Bydesign

1. Go to Purchase order work center.
2. Select any Purchase order view.
3. In the output history tab select the document with status as Error.
4. In the details tab you can see the error message
   
   "Contact your key user to investigate this error.  When the error has been solved your key user should inform you so that you can retry outputting the document.
   BCSOUT_SMTP500
   
   Diagnosis

   An error occurred while transferring the message to the SMTP Server mail-byd-k8s.cis03.rot.s4h.sap.corp. The message has not been delivered to the recipient abc@123.com.

   System Response

   According to the SMTPserver'sreturn code the message cannot beprocesseddue to an error.
   
   The SMTP Server returned the following error message:
   552 5.3.4 Error: message file too big

   Retry sending the document. If the problem persists, create an incident and copy and paste this technical information into the incident."

Common Causes are:

• Large attachments (images, videos, PDFs, etc.)
• Multiple attachments whose combined size exceeds limits (especially after Base64 encoding, which can add ~33% overhead).
• Long email threads with accumulated attachments.
• Server‑specific size limits, such as Gmail’s 25 MB maximum.

• Reduce the total email size (body plus all attachments) to meet the recipient server’s limit.
• Compress attachments into ZIP or RAR archives to decrease size.
• Replace or export images or PDFs at a lower resolution to reduce file size.
• Remove unnecessary or duplicate attachments and trim long email threads.
• After reducing the size, retry sending the document from the Output Management. 

SAP Community:552 5.3.4 – message file too big

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