How To Fix 55402 - Internal error: message classification &1, message number

55402 - Overview

• Message type: E = Error

• Message class: 55 - Messages for development class EENO

• Message number: 402

• Message text: Internal error: message classification &1, message number

What causes this issue?

The message classification for the IS-U message object contains an
invalid message number. This is a program error that can only be
rectified by SAP.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Note the following:
entries leading to the error
message text
and send a problem message to SAP.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message 55402 - Internal error: message classification &1, message number ?

  The SAP error message 55402, which indicates an "Internal error: message classification &1, message number," typically points to an issue within the SAP system that is not directly related to user input or configuration. This error can arise from various underlying causes, including:
  Causes:
  
  System Bugs: There may be a bug in the SAP software that is causing the internal error.
  Data Inconsistencies: Inconsistent or corrupted data in the database can lead to unexpected behavior.
  
  Configuration Issues: Incorrect configuration settings in the system can trigger internal errors.
  Transport Issues: Problems during the transport of objects between systems can lead to inconsistencies.
  Memory Issues: Insufficient memory or resource allocation can cause the system to behave unexpectedly.
  
  Solutions:
  
  Check SAP Notes: Look for relevant SAP Notes in the SAP Support Portal. SAP frequently releases notes that address known issues and provide patches or workarounds.
  System Logs: Review the system logs (transaction SM21) and short dump analysis (transaction ST22) for more detailed