View cluster & event eror

What causes this issue?

Viewcluster event definition errors.

System Response

The Viewcluster was not activated.

How to fix this error?

Correct the event definition error, and reactivate the Viewcluster.
The Viewcluster activation log contains a detailed error list under the
menu item "View -> Display messages -> All".

Error message extract from SAP system. Copyright SAP SE.