CU17 hat meinen Exchange zerschossen

Hi, habe heut Mittag versucht das CU17 zu installieren. Aber bei Schritt5 bricht er immer mit folgender Fehlermeldung ab:
Bin so langsam am Ende mit meinem Wissen.

Fehler:
Der folgende Fehler wurde generiert, als "$error.Clear(); 
$orgVersion = (Get-OrganizationConfig -DomainController $RoleDomainController).AdminDisplayVersion;

# This must not run twice for the same org, because we don't want to
# re-add these extensions after a tenant administrator removes them.
#
# The ExchangeBuild data type has custom comparison logic, so this 
# is more than a simple string comparison.
if ($orgVersion.ExchangeBuild -le "15.01.2021.000")
{
$filetypeslist=@(
".ade",
".adp",
".app",
".appcontent-ms", # Office
".appref-ms", # Windows ClickOnce
".asp",
".aspx",
".asx",
".bas",
".bat",
".cdxml", # PowerShell,  https://docs.microsoft.com/en-us/previous-versions/windows/desktop/wmi_v2/cdxml-overview 
".cer", # Certificates
".chm",
".cmd",
".cnt", # Windows Help
".com",
".cpl",
".crt", # Certificates
".csh",
".der", # Certificates
".diagcab",
".exe",
".fxp",
".gadget",
".grp",
".hlp",
".hpj", # Windows Help
".hta",
".htc",
".inf",
".ins",
".isp",
".its",
".jar",".jnlp", # Java
".js",
".jse",
".ksh",
".lnk",
".mad",
".maf",
".mag",
".mam",
".maq",
".mar",
".mas",
".mat",
".mau",
".mav",
".maw",
".mcf",
".mda",
".mdb",
".mde",
".mdt",
".mdw",
".mdz",
".mht",
".mhtml",
".msc",
".msh",
".msh1",
".msh1xml",
".msh2",
".msh2xml",
".mshxml",
".msi",
".msp",
".mst",
".msu",
".ops",
".osd",
".pcd",
".pif",
".pl",
".plg",
".prf",
".prg",
".printerexport",
".ps1",".ps1xml",".ps2",".ps2xml",".psc1", # PowerShell
".psc2",".psd1",".psdm1",".pssc", # PowerShell
".pst",
".py",".pyc",".pyo",".pyw",".pyz",".pyzw", # Python
".reg",
".scf",
".scr",
".sct",
".settingcontent-ms", # Office
".shb",
".shs",
".theme",
".tmp",
".udl", # Microsoft data link, used by Microsoft Data Access Components
".url",
".vb",
".vbe",
".vbp",
".vbs",
".vsmacros",
".vhd",".vhdx", # Hyper-V
".vsw",
".website",
".webpnp",
".ws",
".wsb", # Windows Sandbox
".wsc",
".wsf",
".wsh",
".xbap",
".xll",
".xnk"
)
#Update OwaMailbox policy
$policies = Get-OwaMailboxPolicy -DomainController $RoleDomainController;
if($policies -ne $null)
{
foreach ($policy in $policies)
{
$blockedFileTypes = $policy.BlockedFileTypes

# Any changes in the below list has to be updated at //depot/E16Ent/sources/dev/data/src/directory/SystemConfiguration/OwaMailboxPolicy.cs
foreach ($extension in $filetypeslist)
{
try
{
if ($policy.AllowedFileTypes.Contains($extension))
{
continue
}
$blockedFileTypes.Add($extension)
}
catch
{
# This probably just means the extension was already in the collection.
# Silently continue to the next one.
}
}
Set-OwaMailboxPolicy -Identity $policy.Identity -BlockedFileTypes $blockedFileTypes -DomainController $RoleDomainController
}
}

#Update OwaVdir Blocked Filetype List (Below Filter used to find the find the corrrect version for Co-existence topology)
$owaVdirs=Get-OwaVirtualDirectory -ShowMailboxVirtualDirectories -server $RoleFqdnOrName -DomainController $RoleDomainController
if($owaVdirs -ne $null)
{
foreach($owaVdir in $owaVdirs)
{
if($owaVdir -ne $null)
{
$blockedFileTypes = $owaVdir.blockedFileTypes
# Any changes in the below list has to be updated at //depot/E16Ent/sources/dev/data/src/directory/SystemConfiguration/OwaMailboxPolicy.cs
foreach ($extension in $filetypeslist)
{
try
{
if ($owaVdir.AllowedFileTypes.Contains($extension))
{
continue
}
$blockedFileTypes.Add($extension)
}
catch
{
# Silently continue to the next one.
}
}
set-owavirtualdirectory -blockedfiletypes $blockedFileTypes -Identity $owaVdir.identity
}
}
}
}
" ausgeführt wurde: "Microsoft.Exchange.Management.Metabase.IISGeneralCOMException: Der Verzeichniseintrag für die Internetinformationsdienste (IIS) kann nicht erstellt werden. Fehlermeldung: Das System kann den angegebenen Pfad nicht finden.
. HResult = -2147024893 ---> System.Runtime.InteropServices.COMException: Das System kann den angegebenen Pfad nicht finden.

bei System.DirectoryServices.DirectoryEntry.Bind(Boolean throwIfFail)
bei System.DirectoryServices.DirectoryEntry.Bind()
bei System.DirectoryServices.DirectoryEntry.RefreshCache()
bei System.DirectoryServices.DirectoryEntry.FillCache(String propertyName)
bei System.DirectoryServices.PropertyCollection.KeysCollection.GetEnumerator()
bei Microsoft.Exchange.Management.Metabase.IisUtility.GetProperties(DirectoryEntry webObj)
--- Ende der internen Ausnahmestapelüberwachung ---
bei Microsoft.Exchange.Management.Metabase.IisUtility.GetProperties(DirectoryEntry webObj)
bei Microsoft.Exchange.Management.SystemConfigurationTasks.WebAppVirtualDirectoryHelper.UpdateFromMetabase(ExchangeWebAppVirtualDirectory webAppVirtualDirectory)
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetWebAppVirtualDirectory`1.StampChangesOn(IConfigurable dataObject)
bei Microsoft.Exchange.Configuration.Tasks.SetObjectTaskBase`2.PrepareDataObject()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetVirtualDirectory`1.PrepareDataObject()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetExchangeVirtualDirectory`1.PrepareDataObject()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetWebAppVirtualDirectory`1.PrepareDataObject()
bei Microsoft.Exchange.Configuration.Tasks.SetTaskBase`1.InternalValidate()
bei Microsoft.Exchange.Configuration.Tasks.SetSystemConfigurationObjectTask`3.InternalValidate()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetExchangeVirtualDirectory`1.InternalValidate()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetWebAppVirtualDirectory`1.InternalValidate()
bei Microsoft.Exchange.Management.SystemConfigurationTasks.SetOwaVirtualDirectory.InternalValidate()
bei Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__91_1()
bei Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)".