How To Fix FB866 - A posting rule could not be determined for external transaction &

FB866 - Overview

• Message type: E = Error

• Message class: FB - Batch Programs

• Message number: 866

• Message text: A posting rule could not be determined for external transaction &

What causes this issue?

The system could not determine a posting rule for the bank's external ID
(transaction code). The external transaction is &V1&, the transaction
type &V2&, and the +/- sign of the line item is &V3&.

System Response

The transaction cannot be posted.

How to fix this error?

Enter the external transaction code in Customizing for Financial
Accounting.

Procedure for System Administrators

To prevent processing from terminating in the future whenever bank
statements with unknown transaction codes are processed, you can define
the external transaction <LB>UNALLOCATED</> in the Customizing activity
<DS:SIMG.FIBLEBS_VC_T028_DC>Make Global Settings for Electronic Bank
Statement</>.

Error message extract from SAP system. Copyright SAP SE.

FB866 - Details

• The SAP error message FB866 indicates that the system could not determine a posting rule for an external transaction. This typically occurs during the processing of financial transactions, such as when posting a document in the Financial Accounting (FI) module. Here’s a breakdown of the cause, potential solutions, and related information for this error:
  
  Cause:
  
  Missing Configuration: The most common cause is that the posting rules for the specific external transaction type have not been defined in the system.
  Incorrect Transaction Type: The external transaction type being used may not be recognized or may not have a corresponding posting rule.
  Inconsistent Data: There may be inconsistencies in the data being posted, such as missing or incorrect account assignments.
  Authorization Issues: The user may not have the necessary authorizations to perform the transaction.
  Custom Development: If there are custom developments or enhancements in the system, they may not be handling the external transaction correctly.
  
  
  Solution:
  
  
  Check Configuration:
  
  Go to the