How To Fix USMD1260 - Data model &1: namespace or package for structure generation not valid

SAP Error Message - Details

• Message type: E = Error

• Message class: USMD1 - Datenmodel

• Message number: 260

• Message text: Data model &1: namespace or package for structure generation not valid

What causes this issue?

We recommend you do not change these entries for data models delivered
by SAP.

System Response

The data model cannot be saved.

How to fix this error?

To enhance a data model delivered by SAP using automatic structure
generation, make the corresponding entries in the view <LS>Prefix and
Packages for Model Enhancements</>.

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.