How To Fix CA_TTE628 - Reverse mapping not possible due to ambiguous external value

SAP Error Message - Details

• Message type: E = Error

• Message class: CA_TTE - TTE Messages

• Message number: 628

• Message text: Reverse mapping not possible due to ambiguous external value

What causes this issue?

Two or more external product tax groups have been assigned to one
internal product tax group.

System Response

How to fix this error?

In Customizing for the TTE:
Choose <DS:SIMG.SIMGMAP_PARTNER>Assign Objects From External Systems</>
Select the relevant external system: <ZK>System ID1</> &V3&, and
<ZK>Tax Type Assignment</> for tax type &V2&.
Select <ZK>Product Tax Group Key Assignment</>.
Adjust the assignments so that each external tax group has a unique
assignment to an internal tax group.
Save your entries.
For an immediate Customizing update, execute
<DS:SIMG.SIMG_REFRESH>Immediate Customizing Refresh</>.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CA_TTE628 - Reverse mapping not possible due to ambiguous external value ?

  The SAP error message CA_TTE628, which states "Reverse mapping not possible due to ambiguous external value," typically occurs in the context of data transfer or mapping processes, particularly when dealing with external values that do not have a clear or unique mapping to internal values in the SAP system.
  Cause:
  
  Ambiguous External Values: The error arises when the system encounters an external value that could correspond to multiple internal values. This ambiguity prevents the system from determining which internal value should be used for the reverse mapping.
  Data Inconsistency: There may be inconsistencies in the data being processed, such as duplicate entries or missing mappings in the configuration.
  Configuration Issues: The mapping configuration may not be set up correctly, leading to multiple potential matches for a single external value.
  
  Solution:
  
  Check Mapping Configuration: Review the mapping configuration in the relevant transaction (e.g., transaction codes like TTE or similar). Ensure that each external value has a unique corresponding internal value.
  Data Cleanup: Identify and resolve any duplicate or ambiguous entries in the external data source. This may involve cleaning up the data to ensure that each external value is unique.
  Enhance Mapping Logic: If necessary, enhance the mapping logic to handle cases where multiple internal values could correspond to a single external value. This might involve adding additional criteria to narrow down the mapping.
  Consult Documentation: Refer to SAP documentation or help resources for specific guidance on the mapping process and how to resolve ambiguities.
  Testing: After making changes, conduct thorough testing to ensure that the mapping works as expected and that the error does not recur.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes that deal with data mapping and transfer, such as TTE (Transfer of External Data).
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP frequently updates its knowledge base with solutions for common problems.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed. Other users may have encountered the same error and can provide insights or solutions.
  
  By addressing the ambiguity in the external values and ensuring a clear mapping to internal values, you should be able to resolve the CA_TTE628 error.