Bei Event funktioniert das Powershell Script nicht richtig

<?xml version="1.0" encoding="UTF-16"?>  
<Task version="1.2" xmlns="http://schemas.microsoft.com/windows/2004/02/mit/task">  
  <RegistrationInfo>
    <Date>2017-11-13T13:19:02.9719722</Date>
    <Author>FIRMA\Benutzer</Author>
  </RegistrationInfo>
  <Triggers>
    <EventTrigger>
      <Enabled>true</Enabled>
      <Subscription>&lt;QueryList&gt;&lt;Query Id="0" Path="Security"&gt;&lt;Select Path="Security"&gt;*[System[Provider[@Name='Microsoft-Windows-Security-Auditing'] and EventID=5139]]&lt;/Select&gt;&lt;/Query&gt;&lt;/QueryList&gt;</Subscription>  
      <ValueQueries>
        <Value name="Class">Event/EventData/Data[@Name='ObjectClass']</Value>  
        <Value name="GUID">Event/EventData/Data[@Name='ObjectGUID']</Value>  
        <Value name="NewOu">Event/EventData/Data[@Name='NewObjectDN']</Value>  
        <Value name="OldOu">Event/EventData/Data[@Name='OldObjectDN']</Value>  
      </ValueQueries>
    </EventTrigger>
  </Triggers>
  <Principals>
    <Principal id="Author">  
      <UserId>FIRMA\Administrator</UserId>
      <LogonType>Password</LogonType>
      <RunLevel>LeastPrivilege</RunLevel>
    </Principal>
  </Principals>
  <Settings>
    <MultipleInstancesPolicy>IgnoreNew</MultipleInstancesPolicy>
    <DisallowStartIfOnBatteries>true</DisallowStartIfOnBatteries>
    <StopIfGoingOnBatteries>false</StopIfGoingOnBatteries>
    <AllowHardTerminate>false</AllowHardTerminate>
    <StartWhenAvailable>false</StartWhenAvailable>
    <RunOnlyIfNetworkAvailable>false</RunOnlyIfNetworkAvailable>
    <IdleSettings>
      <StopOnIdleEnd>true</StopOnIdleEnd>
      <RestartOnIdle>false</RestartOnIdle>
    </IdleSettings>
    <AllowStartOnDemand>true</AllowStartOnDemand>
    <Enabled>true</Enabled>
    <Hidden>false</Hidden>
    <RunOnlyIfIdle>false</RunOnlyIfIdle>
    <WakeToRun>false</WakeToRun>
    <ExecutionTimeLimit>P3D</ExecutionTimeLimit>
    <Priority>7</Priority>
  </Settings>
  <Actions Context="Author">  
    <Exec>
      <Command>powershell</Command>
      <Arguments>-NoProfile -File "C:\Script\MoveToOtherOu.ps1" -OldOu "$(OldOu)" -NewOu "$(NewOu)" -GUID "$(GUID)" -Class "$(Class)"</Arguments>  
    </Exec>
  </Actions>
</Task>

(
    [string]$OldOu,
    [string]$NewOu,
    [string]$GUID,
    [string]$Class
)

$filePath = "C:\Users\benutzer\Documents\logMoveToOtherOu.txt"  
$BaseOu = "OU=firma,DC=intern,DC=firma,DC=de"  

"                                                  " | Out-File -FilePath $filePath -Append  
"-----------------" + (Get-Date).ToUniversalTime() + "-----------------" | Out-File -FilePath $filePath -Append  
"                                                  " | Out-File -FilePath $filePath -Append  

$OldOu | Out-File -FilePath $filePath -Append
$NewOu | Out-File -FilePath $filePath -Append
$GUID | Out-File -FilePath $filePath -Append
$Class | Out-File -FilePath $filePath -Append




if($Class -ne "user")  
{
    Exit
}


$OldOu = $OldOu.Remove(0, $OldOu.IndexOf(',',0)+1)  
$OldOu = $OldOu.Remove(0, $OldOu.IndexOf(',',0)+1)  

if($OldOu -eq $null -or $OldOu -eq "")  
{
    Exit
}

$NewOu = $NewOu.Remove(0, $NewOu.IndexOf(',',0)+1)  
$NewOu = $NewOu.Remove(0, $NewOu.IndexOf(',',0)+1)  

if($NewOu -eq $null -or $NewOu -eq "")  
{
    Exit
}


$user = Get-ADUser -Identity $GUID

function GetCityName($City)
{
    switch($City)
    {
        "Berlin" {return "BER"}  
        "München" {return "MUN"}  
        "London" {return "LON"}  
        "Madrid" {return "MAD"}  
        "Paris" {return "PAR"}  
        "Warschau" {return "WAR"}  
        default { return $false}


    }
}

function GetGroupName($OuName)
{
    $groupName = ""  

    $OuArray = $OuName.Split(",")  

    $City = GetCityName($OuArray[-6].Split("=")[1])  
    if($City -eq $false)
    {
        return $false
    }
    
    $specialGroup = ""  
    $department = ""  
    if($OuArray[-7].Split("=")[1] -eq "Special Groups")  
    {
        $specialGroup = "SP"  
        $groupName = "GRP_" + $City + "_" + $specialGroup  
        for($counter = $OuArray.Count - 8; $counter -ge 0; $counter--)
        {
            $item = $OuArray[$counter].Split("=")[1]  
            $groupName = $groupName + "_" + $item  
        }
    }
    else
    {
        $groupName = "GRP_" + $City  
        for($counter = $OuArray.Count - 7; $counter -ge 0; $counter--)
        {
            $item = $OuArray[$counter].Split("=")[1]  
            $groupName = $groupName + "_" + $item  
        }
    }
    
    return $groupName
    
}

$OldGroupName = GetGroupName($OldOu)
$NewGroupName = GetGroupName($NewOu)

$OldGroupName | Out-File -FilePath $filePath -Append
$NewGroupName | Out-File -FilePath $filePath -Append

if($NewGroupName -eq $false)
{
    $text = "Gruppenname leer"  
    $text | Out-File -FilePath $filePath -Append
    Exit
}
#Get-ADPrincipalGroupMembership $user | select name | Out-File -FilePath $filePath -Append
try
{
    Remove-ADGroupMember -Identity $OldGroupName -Members $user -Confirm: $false
}
catch
{
    $FailMessage = "Fail: " + $_.Exception.Message + " " + $_.Exception.ItemName  
    $FailMessage | Out-File -FilePath $filePath -Append
}

try
{
    if((Get-ADGroup -SearchBase $BaseOu -Filter * | select name | where name -eq $NewGroupName) -ne $true) 
    {
        New-ADGroup -Name $NewGroupName -Path $NewOu -GroupCategory Security -GroupScope Global
    }
    
}
catch
{
    $FailMessage = "Fail: " + $_.Exception.Message + " " + $_.Exception.ItemName  
    $FailMessage | Out-File -FilePath $filePath -Append
}
try
{
    Add-ADGroupMember -Identity $NewGroupName -Members $user
}
catch
{
    $FailMessage = "Fail: " + $_.Exception.Message + " " + $_.Exception.ItemName  
    $FailMessage | Out-File -FilePath $filePath -Append
}