How To Fix CNV_MBT166 - RFC-error to destination &1: &2

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_MBT - PCL message class

• Message number: 166

• Message text: RFC-error to destination &1: &2

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_MBT166 - RFC-error to destination &1: &2 ?

  The SAP error message CNV_MBT166 indicates an RFC (Remote Function Call) error when trying to connect to a specified destination. This error typically occurs during data migration or conversion processes, particularly when using the SAP Landscape Transformation (SLT) or other migration tools.
  Cause:
  The error can be caused by several factors, including:
  
  Network Issues: There may be network connectivity problems between the source and target systems.
  RFC Destination Configuration: The RFC destination may not be correctly configured in the SAP system. This includes incorrect parameters such as the target system's IP address, port, or user credentials.
  Authorization Issues: The user credentials used for the RFC connection may not have the necessary authorizations to perform the required operations.
  System Availability: The target system may be down or not reachable due to maintenance or other issues.
  Firewall Restrictions: Firewalls or security settings may be blocking the RFC connection.
  
  Solution:
  To resolve the CNV_MBT166 error, you can follow these steps:
  
  
  Check Network Connectivity:
  
  Ensure that the source and target systems can communicate over the network. You can use tools like ping or telnet to test connectivity.
  
  
  
  Verify RFC Destination Configuration:
  
  Go to transaction SM59 in the SAP GUI.
  Check the configuration of the RFC destination that is causing the error. Ensure that the connection type, target host, and service/port are correctly set.
  Test the connection from SM59 to see if it is successful.
  
  
  
  Review User Credentials:
  
  Ensure that the user credentials used for the RFC connection have the necessary authorizations. You can check this in transaction SU01.
  
  
  
  Check System Availability:
  
  Verify that the target system is up and running. You can check the system status in the SAP system or consult with your system administrator.
  
  
  
  Firewall and Security Settings:
  
  Ensure that there are no firewall rules or security settings that are blocking the RFC connection. Consult with your network/security team if necessary.
  
  
  
  Review Logs:
  
  Check the system logs (transaction SM21) and the developer trace (transaction ST22) for any additional error messages that might provide more context about the issue.
  
  
  
  Related Information:
  
  RFC (Remote Function Call): A protocol used in SAP systems to enable communication between different SAP systems or between SAP and non-SAP systems.
  SM59: Transaction code used to manage and configure RFC destinations in SAP.
  SU01: Transaction code used to manage user accounts and authorizations in SAP.
  SM21: Transaction code for viewing system logs.
  ST22: Transaction code for analyzing dump analysis.
  
  If the issue persists after following these steps, it may be beneficial to consult SAP support or your internal SAP Basis team for further assistance.