How To Fix /SAPCND/CUSTOMIZING303 - Unknown RFC error

SAP Error Message - Details

• Message type: E = Error

• Message class: /SAPCND/CUSTOMIZING -

• Message number: 303

• Message text: Unknown RFC 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.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPCND/CUSTOMIZING303 - Unknown RFC error ?

  The SAP error message /SAPCND/CUSTOMIZING303 Unknown RFC error typically indicates an issue with Remote Function Call (RFC) communication between systems in an SAP environment. This error can arise due to various reasons, including configuration issues, network problems, or authorization issues.
  Possible Causes:
  
  Network Issues: There may be connectivity problems between the SAP systems involved in the RFC call.
  RFC Destination Configuration: The RFC destination may not be correctly configured in transaction SM59. This includes incorrect parameters, such as the target system's IP address, port, or logon credentials.
  Authorization Issues: The user credentials used for the RFC connection may not have the necessary authorizations to perform the requested operation.
  System Availability: The target system may be down or not reachable due to maintenance or other issues.
  SAP Kernel or Patch Level: There may be a bug in the SAP kernel or a missing patch that affects RFC communication.
  
  Solutions:
  
  Check Network Connectivity: Ensure that the network connection between the