2351330 - "An error occurred while initializing the system provisioning step" when starting System Refresh in LaMa, (LVM)

Upon starting a System Refresh by clicking on the according button in LaMa (in older version LVM), an error is thrown:

"[Exception(s)]
An error occurred while initializing the system provisioning step.
[...]
Cause(s):
java.lang.ClassCastException: Cannot cast class com.sap.nw.lm.aci.engine.api.controller.request.OpRequest
(loader sap.com/tc~vcm~engine~app@com.sap.engine.boot.loader.ResourceMultiParentClassLoader@4c27e7@alive)
to class com.sap.nw.lm.aci.engine.api.controller.request.OpRequest
(loader sap.com/tc~vcm~engine~app@com.sap.engine.boot.loader.ResourceMultiParentClassLoader@2da778c@unregistered)"

Another error message can be:

"Manager is not yet initialized [AuthorizationRuntimeException]

error stack:
failed to get VCM controller
caused by Manager is not yet initialized
[com.sap.nw.lm.aci.engine.base.exception.AuthorizationRuntimeException]"

LVM 2.1 Enterprise Edition, LaMa 3.0

LaMa, LVM, SUM, patch, deployment, ErrorInfo.txt, ErrorInfo.xml, ExceptionInfo, Manager is not yet initialized , KBA , BC-VCM-LVM , Landscape Virtualization Management , Problem