Private Const PROCESS_DUP_HANDLE = &H40
Private Const PROCESS_SET_INFORMATION = &H200
 
Private Declare Function GetCurrentProcessId Lib "KERNEL32" () As Long
 
Private Declare Function OpenProcess Lib "KERNEL32" ( _
  ByVal dwDesiredAccess As Long, _
  ByVal bInheritHandle As Long, _
  ByVal dwProcessId As Long) As Long
 
Private Declare Function SetPriorityClass Lib "KERNEL32" ( _
  ByVal hProcess As Long, _
  ByVal dwPriorityClass As Long) As Long
 
Private Declare Function CloseHandle Lib "KERNEL32" ( _
  ByVal hObject As Long) As Long
 
' Prioritätsstufen
Public Enum PriorityClass
  IDLE_PRIORITY_CLASS = &H40
  NORMAL_PRIORITY_CLASS = &H20
  HIGH_PRIORITY_CLASS = &H80
  REALTIME_PRIORITY_CLASS = &H100
End Enum

Public Sub SetPriority(ByVal nPriority As PriorityClass)
  Dim nPID As Long
  Dim hProcess As Long
 
  ' ProzessID ermitteln
  nPID = GetCurrentProcessId()
 
  ' Prozess-Handle
  hProcess = OpenProcess(PROCESS_DUP_HANDLE + PROCESS_SET_INFORMATION, 1, nPID)
  If hProcess <> 0 Then
    ' Prozess-Priorität setzen
    SetPriorityClass hProcess, nPriority
  End If
 
  ' Handle wieder freigeben
  CloseHandle hProcess
End Sub