2485327 - JmxSecurityException in Identity Management when changing UME datasource

The UME datasource was changed as per note 718383 and the Identity Management stopped working properly. Trying to access the Identity Management it gives the error:

Error: A required service for the identity management user interface is not available. Contact your system administrator. SeeSAP Notes 869852 and 963174

When trying to open another tab from Identity Management, the following error appears:

com.sap.tc.webdynpro.services.exceptions.ApplicationFaultException: wdDoInit: exception thrown in this user coding area
Caused by: com.sap.engine.services.jmx.exception.JmxSecurityException: Caller <USER> not authorized, requiredpermission missing (javax.management.MBeanPermission-#SAP_ITSAMJ2eeClusterJ2eeInstancePartComponent[:SAP_ITSAMJ2eeCluster.CreationClassName=SAP_ITSAMJ2eeCluster,SAP_ITSAMJ2eeCluster.Name=<SID>.SystemHome.<HOSTNAME>,cimclass=SAP_ITSAMJ2eeCluster,j2eeType=J2EEServer,name=<SID>,type=SAP_ITSAMJ2eeCluster,version=1.0] getAttribute)

Where <USER> is the user that you logged on, or the user in Run-As Identity configuration.

SAP NetWeaver Application Server Java

Caused by: com.sap.engine.services.jmx.exception.JmxSecurityException: Caller not authorized, required permission missing ApplicationFaultException: wdDoInit: exception thrown in this user coding area SAP_ITSAMJ2eeClusterJ2eeInstancePartComponent srm A required service for the identity management user interface is not available 869852 and 963174 portal netweaver java as application server sap action role group grup authorization user , KBA , BC-JAS-SEC-UME , User Management Engine , Problem