How To Fix B1605 - No connection to R/2 (TXCOM destination &); see SAP system log

SAP Error Message - Details

• Message type: E = Error

• Message class: B1 - ALE group messages

• Message number: 605

• Message text: No connection to R/2 (TXCOM destination &); see SAP system log

What causes this issue?

No connection could be made to the R/2 system with TXCOM destination
&v1&.

How to fix this error?

Check that both the receiving R/2 system and the connection to R/2 are
available.
If they are, then check the side info for the SAP gateway with the TXCOM
destination &v1& and the SNA configuration.
The sending of this IDoc is restarted automatically as long as the
maximum repeat count is not exceeded.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message B1605 - No connection to R/2 (TXCOM destination &); see SAP system log ?

  The SAP error message B1605 indicates that there is no connection to the R/2 system from the R/3 system (or S/4HANA). This error typically occurs when there is an issue with the communication setup between the two systems, which can be due to various reasons such as configuration errors, network issues, or problems with the RFC (Remote Function Call) destination.
  Causes:
  
  RFC Destination Configuration: The RFC destination for the R/2 system may not be configured correctly in the R/3 system.
  Network Issues: There may be network connectivity issues preventing the R/3 system from reaching the R/2 system.
  R/2 System Down: The R/2 system may be down or not running.
  Authorization Issues: The user credentials used for the connection may not have the necessary authorizations.
  SAP Kernel or Patch Issues: There may be compatibility issues between the SAP kernels or patches installed on the systems.
  
  Solutions:
  
  
  Check RFC Destination:
  
  Go to transaction SM59 in the R/3 system.
  Verify the configuration of the RFC destination pointing to the R/2 system.
  Test the connection using the "Connection Test" option.
  
  
  
  Check Network Connectivity:
  
  Ensure that the network connection between the R/3 and R/2 systems is active.
  Use tools like ping or traceroute to check connectivity.
  
  
  
  Check R/2 System Status:
  
  Ensure that the R/2 system is up and running.
  Check the R/2 system logs for any errors or issues.
  
  
  
  Review User Authorizations:
  
  Ensure that the user credentials used for the RFC connection have the necessary authorizations in both systems.
  
  
  
  Check SAP Notes:
  
  Look for any relevant SAP Notes that may address known issues with the specific versions of the systems you are using.
  
  
  
  Review System Logs:
  
  Check the system logs in both the R/3 and R/2 systems for any additional error messages that may provide more context.
  
  
  
  Consult Basis Team:
  
  If the issue persists, consult your SAP Basis team for further investigation and troubleshooting.
  
  
  
  Related Information:
  
  
  Transaction Codes:
  
  SM59: To manage RFC destinations.
  SM21: To view system logs.
  ST22: To check for dumps that may provide additional information.
  
  
  
  Documentation: Refer to SAP Help documentation for detailed information on configuring RFC connections and troubleshooting connectivity issues.
  
  
  By following these steps, you should be able to identify and resolve the cause of the B1605 error message.