How To Fix TB404 - No connection to remote system or error in communications

TB404 - Overview

• Message type: E = Error

• Message class: TB - SM31 table maintenance messages

• Message number: 404

• Message text: No connection to remote system or error in communications

What causes this issue?

No link to remote system &v1& or incorrect communications

System Response

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

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.

TB404 - Details

• The SAP error message TB404, which indicates "No connection to remote system or error in communications," typically arises when there is a failure in the communication between SAP systems or between an SAP system and an external system. This can occur in various scenarios, such as during remote function calls (RFC), IDoc processing, or when using other communication protocols.
  Causes of TB404 Error
  
  
  Network Issues: Problems with the network connection, such as firewalls blocking traffic, network outages, or incorrect routing.
  
  
  Configuration Errors: Incorrect settings in the RFC destination or the logical system configuration in SAP.
  
  
  System Availability: The remote system may be down or not reachable due to maintenance or other issues.
  
  
  Authorization Issues: The user or service account may not have the necessary permissions to access the remote system.
  
  
  Protocol Mismatch: Incompatibility between the communication protocols used by the systems.
  
  
  SAP Gateway Issues: Problems with the SAP Gateway service, which is responsible for handling communication requests.
  
  
  Solutions