This program cannot be run in the SAP standard client

What causes this issue?

The Customizing settings in client 000 of the standard SAP System
supplied cannot be changed. For this reason, this program cannot be
run.

System Response

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

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.