3707558 - Custom Logic publish fails with internal error after S/4HANA upgrade

After upgrading from SAP S/4HANA 2020 to SAP S/4HANA 2025, users encounter an issue when attempting to publish code modifications in the Custom Logic application.

The issue occurs while adjusting enhancements reported in SPAU_ENH, specifically affecting Cloud BAdI implementations that existed before the upgrade.

When selecting Publish in the Custom Logic app, the following error message is displayed:

• "An internal error occurred. Report an incident for BC-SRV-APS-EXT-BL."

As part of the analysis and troubleshooting, the following steps were also performed:

1. Use Fiori app "Register Extension for Transport", select the "Custom Logic item", and use "assign to transport request -> for full retransport" in order to capture all the needed artifacts in a new transport request.
2. Add the affected user to the assigned Transport request

But the issue still persists.

And there are no authorization failures recorded in SU53, as referenced in SAP Note 3600195, indicating that the issue is not authorization-related. 

SAP S/4HANA On-Premise

Upgrade from SAP S/4HANA 2020 to SAP S/4HANA 2025

Custom Logic application 

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