How To Fix WL402 - Workflow '&' no. & step no. &: Error in expression '&' or '&'

SAP Error Message - Details

• Message type: E = Error

• Message class: WL - Workflow: run-time messages

• Message number: 402

• Message text: Workflow '&' no. & step no. &: Error in expression '&' or '&'

What causes this issue?

One of the two expressions could not be evaluated.

System Response

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

INCLUDE NA_WF_ERROR OBJECT DOKU ID TX

How to fix this error?

Precise information on the type of error can be found in the preceding
message.
Correct the error and continue the interrupted workflow. If it is not
possible to make a correction, start the workflow again.
INCLUDE NA_WF-ADMINISTRATOR OBJECT DOKU ID TX

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message WL402 - Workflow '&' no. & step no. &: Error in expression '&' or '&' ?

  The SAP error message WL402 typically indicates that there is an issue with a workflow expression in the specified step of a workflow. This error can occur for various reasons, and understanding the cause and potential solutions can help you resolve it effectively.
  Cause:
  
  Syntax Error: The expression used in the workflow step may contain a syntax error, such as missing operators, incorrect function calls, or invalid variable names.
  Data Type Mismatch: The expression may be trying to perform operations on incompatible data types (e.g., trying to perform arithmetic on a string).
  Missing Variables: The expression may reference variables that are not defined or are not available in the current context of the workflow.
  Logical Errors: There may be logical errors in the expression that prevent it from being evaluated correctly.
  Workflow Configuration Issues: The workflow itself may not be configured correctly, leading to issues when executing the expressions.
  
  Solution:
  
  Check the Expression Syntax: Review the expression in the workflow step for any syntax errors. Ensure that all operators and functions are used correctly.
  Validate Data Types: Ensure that the data types of the variables used in the expression are compatible with the operations being performed.
  Verify Variable Availability: Check that all variables referenced in the expression are defined and available in the workflow context.
  Debugging: Use the workflow debugging tools in SAP to step through the workflow and identify where the error occurs. This can help pinpoint the exact issue with the expression.
  Review Workflow Configuration: Ensure that the workflow is configured correctly, including all necessary steps and conditions.
  Consult Documentation: Refer to SAP documentation or help resources for specific guidance on the functions and expressions being used in the workflow.
  
  Related Information:
  
  Transaction Codes: You can use transaction codes like SWI1 (Work Item Selection) or SWI2_FREQ (Work Item Selection - Frequency) to monitor and analyze workflow instances.
  Workflow Logs: Check the workflow logs for additional details about the error. This can provide insights into what went wrong during execution.
  SAP Notes: Search for relevant SAP Notes that may address known issues related to the WL402 error message.
  Community Forums: Consider reaching out to SAP community forums or support for additional assistance if the issue persists.
  
  By following these steps, you should be able to identify and resolve the issue causing the WL402 error in your SAP workflow.