SAP Message WB2B_TEW046 - Error in Customizing for enhancement classes

Diagnosis
A Customizing error occurred.

System Response
The function is terminated.

Procedure
INCLUDE ISR_VERWALTUNG

Procedure for System Administration
In Customizing, enhancement class &v1& was entered, but this does notexist in the system. Please ensure that a typing error was not made(define enhancement class).