Findong if a winow is open

[AliBail]

Hi, basically, I need to know, how I can check if a window is open, and if it is do something.

The window is in another program

[Megatron]

Use the FindWindowEx function.

Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
 
Private Sub Command1_Click()
    Dim hApp as Long
    hApp = FindWindowEx(0, 0, "ClassName", "WindowName")
    If hApp <> 0 Then MsgBox "Window is open
End Sub