No standard user type defined.

What causes this issue?

Failed to identify a standard user type that is assigned for
non-classified users.

System Response

A system measurement cannot be carried out.
The user list cannot be displayed.

How to fix this error?

Go to the USMM settings and in section <ZK>Price Lists</>, select a
default user type that can be assigned for non-classified users.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.