Introduction
Verify if the windows or form is loaded.
Declaration Function FindWindow
Private Declare Function FindWindow Lib "USER32" Alias "FindWindowA" _
(ByVal lpszClassName As String, ByVal lpszWindow As String) As Long
Call the function:
If FindWindow(vbNullString, Caption) Then
msgbox "Yes"
Else
msgbox "No"
End If
You can verify if a window or form is open not only from visual basic, from windows itself
For example you can verify if the application CALC.EXE is loaded.
Se puede verificar no solo los formularios abeirtos dentro de Visual Basic, sino tambien cualquier ventana que se encuentre abierta en Windows.