How To Fix UX289 - External number must be entered for internal number assignment

SAP Error Message - Details

• Message type: E = Error

• Message class: UX - TR: Business Partner and Loan Conversion

• Message number: 289

• Message text: External number must be entered for internal number assignment

What causes this issue?

You want to transfer a record designated for internal number
assignment. No value was transferred for the field EXTPARTNR. This
means that there would be no way of finding this record in the system,
since the link to the external number that is known by the user would
be missing.

System Response

The transfer is rejected.

How to fix this error?

Transfer the external number for this record.

Error message extract from SAP system. Copyright SAP SE.