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'System & API - How to Change the Priority of any Running Process

Option Explicit
 
Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Declare Function OpenProcess Lib "kernel32" (ByVal dwDesiredAccess As Long, _
    ByVal bInheritHandle As Long, ByVal dwProcessId As Long) As Long
Declare Function GetWindowThreadProcessId Lib "user32" (ByVal hwnd As Long, _
    lpdwProcessId As Long) As Long
Declare Function SetPriorityClass Lib "kernel32" (ByVal hProcess As Long, _
    ByVal dwPriorityClass As Long) As Long
Public Const REALTIME_PRIORITY_CLASS = &H100
Public Const HIGH_PRIORITY_CLASS = &H80
Public Const NORMAL_PRIORITY_CLASS = &H20
Public Const IDLE_PRIORITY_CLASS = &H40
 
Private Sub Form_Load()
    Dim lRet As Long, lProcessID As Long, lProcessHandle As Long
    'You can replace me.hwnd with the handle of the
    'window that you want to change its priority
    GetWindowThreadProcessId Me.hwnd, lProcessID
    'Get the process handled
    lProcessHandle = OpenProcess(0, False, lProcessID)
    'Sets the priority
    'use any priority from the following (from the highest priority to the lowest):
    'REALTIME_PRIORITY_CLASS
    'HIGH_PRIORITY_CLASS
    'NORMAL_PRIORITY_CLASS
    'IDLE_PRIORITY_CLASS
    'if lRet <> 0 then the changing operation action was successful
    lRet = SetPriorityClass(lProcessHandle, HIGH_PRIORITY_CLASS)
    'Close the handle so system retains accurate count of open handles to process.
    'Returns non-zero if successful
    lRet = CloseHandle(lProcessHandle)
End Sub