Powershell - User Remote abmelden

foreach ($server in $server) {
    query user /server:$SERVER 2>&1 | select -skip 1 | foreach {logoff ($_ -split "\s+")[-6] /server:$SERVER}  
    [string] $strUsername = ""  
    [string] $strSitzungsId = ""  
    [array] $aIgnorUsername = @("services","console","rdp","administrator")  
    query session /server:$SERVER | Select-String "$username\s+(\w+)" | Select-Object -Skip 1 | Foreach {  
        $strUsername = $_.Matches.Groups[1].Value
        if($aIgnorUsername -notcontains $strUsername) {
            $strSitzungsId = ((quser /server:$SERVER | ? { $_ -match $strUsername} ) -split ' +')[2]  
            if($strSitzungsId) {
                Write-host "Benutzer $strUsername wird abgemeldet."  
                logoff $strSitzungsId /server:$SERVER
            }
        }
    }
}