How To Fix WT238 - Error while starting RFC: Unknown error

SAP Error Message - Details

• Message type: E = Error

• Message class: WT - Retail: Replenishment

• Message number: 238

• Message text: Error while starting RFC: Unknown error

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message WT238 - Error while starting RFC: Unknown error ?

  The SAP error message WT238: Error while starting RFC: Unknown error typically occurs in the context of Warehouse Management (WM) or Extended Warehouse Management (EWM) when an RFC (Remote Function Call) connection fails to start or execute properly, but the system cannot determine the exact cause, hence the "Unknown error" part.
  
  Cause
  
  
  RFC Destination Issues:
  
  The RFC destination used to connect to the remote system (or the same system) is incorrectly configured or inactive.
  The target system is down or unreachable due to network issues.
  The user credentials for the RFC destination are invalid or locked.
  
  
  
  Authorization Problems:
  
  The user assigned to the RFC destination lacks the necessary authorizations to execute the function module.
  
  
  
  System or Client Mismatch:
  
  The RFC destination points to a wrong system or client.
  The function module being called is not available or not released in the target system.
  
  
  
  Technical Issues:
  
  SAP kernel or gateway problems.
  Network interruptions or firewall blocking the connection.
  SAP Gateway service not running on the target system.
  
  
  
  Incorrect or Missing Parameters:
  
  The RFC call is made with incorrect parameters or missing mandatory data.
  
  
  
  
  Solution
  
  
  Check RFC Destination:
  
  Go to transaction SM59.
  Test the RFC destination used in the process.
  Ensure the connection test is successful.
  Verify the target system, client, user, and logon details.
  
  
  
  Verify User Authorizations:
  
  Check the user assigned to the RFC destination.
  Ensure the user has the necessary roles and authorizations to execute the required function modules.
  
  
  
  Check System Availability:
  
  Confirm that the target system is up and running.
  Check network connectivity between the systems.
  Ensure SAP Gateway is active (transaction SMGW).
  
  
  
  Review Logs and Traces:
  
  Check system logs in SM21 for related errors.
  Use ST22 to check for any dumps related to the RFC call.
  Use SM58 to check for transactional RFC (tRFC) errors.
  
  
  
  Check Function Module:
  
  Verify that the function module being called exists and is released for remote calls.
  Check if any recent transport or changes affected the function module.
  
  
  
  Restart SAP Gateway or System:
  
  If the gateway is down or unstable, restart the SAP Gateway service.
  In some cases, a system restart may be required.
  
  
  
  Network and Firewall:
  
  Ensure no firewall or network device is blocking the RFC ports.
  Check with your network team if necessary.
  
  
  
  
  Related Information
  
  
  Transaction Codes:
  
  SM59 – RFC Destinations
  SMGW – Gateway Monitor
  SM21 – System Log
  ST22 – ABAP Dump Analysis
  SM58 – tRFC Monitor
  
  
  
  SAP Notes:
  
  Search for SAP Notes related to WT238 or RFC errors in the SAP Support Portal.
  Common notes may address specific kernel or patch-level issues.
  
  
  
  Documentation:
  
  SAP Help Portal for WM/EWM and RFC configuration.
  SAP Community forums for similar issues and solutions.
  
  
  
  
  Summary
  
  
  
  Aspect
  Details
  
  
  
  
  Error
  WT238: Error while starting RFC: Unknown error
  
  
  Cause
  RFC destination misconfiguration, authorization issues, system unavailability, network problems
  
  
  Solution
  Check and test RFC destination (SM59), verify user authorizations, check system and network status, review logs, restart gateway if needed
  
  
  Related Info
  Use SM59, SMGW, SM21, ST22, SM58; check SAP Notes and documentation
  
  
  
  
  If you provide more context (e.g., when exactly the error occurs, system landscape, RFC destination details), I can help with a more targeted troubleshooting approach.