Newest version, Citrix only, but removes all the hung sessions in the farm without attached users and in an 'Application Not Running' state

Remove-BadWinlogonSession.ps1

#Requires -Module Citrix.Broker.Admin.V2

function Remove-BadWinLogonSession {
    <#
        .DESCRIPTION
            This function searches for sessions that are in a NoApps state (Applications Not Running) and
            also do not have a BrokeringUserName.  This state indicates a session with a hung winlogon.exe
            process that is not "owned" by anyone.  Sessions in a NoApps state, but have a BrokeringUserName
            are valid inactive sessions and are not modified.

        .SYNOPSIS
            This function removes winlogon processes for dead sessions.

        .PARAMETER ControllerName
            This is the Citrix Delivery Controller to access for this process.

        .NOTES
            The script uses CIM and accesses both the Citrix and CIMV2 namespaces.
        .EXAMPLE
            PS C:\> Remove-BadWinlogonSession -ControllerName CTXDDC01 -Verbose
            VERBOSE: This session (87) is a DEAD session; the processID is (45208); stopping this process
            VERBOSE: This session (78) is a LIVE session; the processID is (6664)
            VERBOSE: This session (94) is a LIVE session; the processID is (47824)
            VERBOSE: This session (106) is a LIVE session; the processID is (24296)
            VERBOSE: This session (78) is a DEAD session; the processID is (49184); stopping this process
            VERBOSE: This session (63) is a LIVE session; the processID is (46596)
            VERBOSE: This session (87) is a LIVE session; the processID is (37556)
            VERBOSE: This session (57) is a DEAD session; the processID is (16108); stopping this process
            VERBOSE: This session (96) is a DEAD session; the processID is (45984); stopping this process
            VERBOSE: This session (87) is a DEAD session; the processID is (42556); stopping this process
            VERBOSE: This session (104) is a DEAD session; the processID is (28000); stopping this process
            VERBOSE: This session (40) is a LIVE session; the processID is (34572)
        .INPUTS
            [string]
        .OUTPUTS
            None
    #>

    [cmdletbinding()]
    param(
        [parameter(ValueFromPipelineByPropertyName, Mandatory)]
        [string]$ControllerName
    )

    $DeadSessionParams      = @{
        AdminAddress        = $ControllerName
        AppState            = 'NoApps'
        BrokeringUserName   = $null
    }

    $DeadSessionHosts = Get-BrokerSession @DeadSessionParams |
        Where-Object { $null -eq $_.BrokeringUserName } |
        Select-Object -ExpandProperty HostedMachineName

    foreach ($thisHost in $DeadSessionHosts) {
        Write-Verbose -Message ('Processing ({0})' -f $thisHost)

        $CitrixSessionSplat = @{
            ComputerName       = $thisHost
            NameSpace          = 'Root\Citrix\hdx'
            ClassName          = 'Citrix_Sessions'
        }
        $CitrixSessionIDList   = (Get-CimInstance @CitrixSessionSplat).SessionID

        $WinLogonSplat = @{
            ComputerName       = $thisHost
            ClassName          = 'Win32_Process'
            Filter             = "Caption = 'winlogon.exe' AND SessionID > 1"
        }
        $WinLogonList          = Get-CimInstance @WinLogonSplat

        foreach ($SessionID in $WinLogonList.SessionID) {

            $thisSession = $WinLogonList | Where-Object SessionID -eq $SessionID

            if ($CitrixSessionIDList -Contains $SessionID) {
                $Message = 'This session ({0}) is a LIVE session on {1}' -f $thisSession.SessionId, $thisHost
            }
            else {
                $Message = 'This session ({0}) is a DEAD session on {1}; the processID for winlogon.exe is ({2}); stopping this process' -f $thisSession.SessionId, $thisHost, $thisSession.ProcessId
                $thisSession | Remove-CimInstance
            }
            Write-Verbose -Message $Message
        }
    }
}