Routine & (Table & could not be expanded)

What causes this issue?

It was not possible to delete a table or structure included in the
table.

System Response

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

WHAT_TO_DO&
Check whether the included table or structure is active and whether it
contains fields.

Error message extract from SAP system. Copyright SAP SE.