SoloCodigo

Option Explicit
'This code is developed by Ivan Uzunov
'e-mail: kicheto@goatrance.com
'Just add this code on a form add a Command1 and press F5

Private Declare Function SystemParametersInfo Lib "user32" Alias "SystemParametersInfoA" (ByVal uAction As Long, ByVal uParam As Long, ByVal lpvParam As Any, ByVal fuWinIni As Long) As Long
    Private Const SPI_SETDESKWALLPAPER = 20

Private Sub Command1_Click()

    Dim WallPaper As Long
    Dim strAppPath As String
    ' Always set working directory to directory containing the application.
    ChDrive CurDir(App.Path)
    ChDir App.Path
    strAppPath = App.Path & IIf(Right$(App.Path, 1) <> "\", "\", "")
   
    'Just change "C:\REDCAP.bmp" with a existing bitmap on your computer
    WallPaper = SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, strAppPath & "REDCAP.bmp", 0)
End Sub