How To Fix 0T138 - Target system '&1'/target domain '&2' unknown

0T138 - Overview

• Message type: E = Error

• Message class: 0T - WBO Configuration Editor / SE06

• Message number: 138

• Message text: Target system '&1'/target domain '&2' unknown

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.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

0T138 - Details

• The SAP error message 0T138, which states "Target system '&1'/target domain '&2' unknown," typically occurs in the context of SAP system landscape management, particularly when dealing with system connections, transport routes, or system configurations. Here’s a breakdown of the cause, potential solutions, and related information:
  
  Cause:
  
  Incorrect Configuration: The target system or domain specified in the transport request or configuration is not correctly defined in the SAP system landscape.
  Missing System Entry: The target system may not be registered in the Transport Management System (TMS) or the System Landscape Directory (SLD).
  Typographical Errors: There may be a typo in the system name or domain specified in the transport request or configuration.
  Network Issues: There could be network connectivity issues preventing the source system from recognizing the target system.
  Authorization Issues: The user may not have the necessary authorizations to access the target system.
  
  
  Solution:
  
  
  Check System Configuration:
  
  Go to the TMS configuration (transaction code STMS).
  Verify that the target system