Released: June 2021 Quarterly Exchange Updates

Hello,

currently I fail already in the preparation for the actual setup:
Schema was successfully updated from CU19 to CU21
Setup.EXE /PrepareAD /IAcceptExchangeServerLicenseTerms keeps aborting:

GUI Step 1 from 18:
Der folgende Fehler wurde generiert, als „$error.Clear();
$createTenantRoot = ($RoleIsDatacenter -or $RoleIsPartnerHosted);
$createMsoSyncRoot = $RoleIsDatacenter;

#$RoleDatacenterIsManagementForest is set only in Datacenter deployment; interpret its absense as $false
[bool]$isManagementForest = ($RoleDatacenterIsManagementForest -eq $true);

if ($RolePrepareAllDomains)
{
initialize-DomainPermissions -AllDomains:$true -CreateTenantRoot:$createTenantRoot -CreateMsoSyncRoot:$createMsoSyncRoot -IsManagementForest:$isManagementForest;
}
elseif ($RoleDomain -ne $null)
{
initialize-DomainPermissions -Domain $RoleDomain -CreateTenantRoot:$createTenantRoot -CreateMsoSyncRoot:$createMsoSyncRoot -IsManagementForest:$isManagementForest;
}
else
{
initialize-DomainPermissions -CreateTenantRoot:$createTenantRoot -CreateMsoSyncRoot:$createMsoSyncRoot -IsManagementForest:$isManagementForest;
}
“ ausgeführt wurde: „System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
bei Microsoft.Exchange.Management.Tasks.SetupTaskBase.LogReadObject(ADRawEntry obj)
bei Microsoft.Exchange.Management.Tasks.InitializeDomainPermissions.InternalProcessRecord()
bei Microsoft.Exchange.Configuration.Tasks.Task.b__91_1()
bei Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)
bei Microsoft.Exchange.Configuration.Tasks.Task.ProcessTaskStage(TaskStage taskStage, Action initFunc, Action mainFunc, Action completeFunc)
bei Microsoft.Exchange.Configuration.Tasks.Task.ProcessRecord()
bei System.Management.Automation.CommandProcessor.ProcessRecord()“.

Since I had not installed the CU20 so far, I have of course tried to make the preparations for the CU20, this works fine.
Currently I do not know where to start. Permissions are almost impossible (upgrade from CU19 to CU20 has just worked).

Does anyone have any ideas?

Thanks & greetings

Mario