Image Loading Error

I can't get an image to load into my program. The program uses the GUI codes with a canvas. Here's a small example of my code:

Global Toolbarimage=LoadAnimImage("data\toolbar.png",24,30,0,70)
MaskImage ToolbarImage,255,255,255

Global window=createwindow("Window",0,0,700,500,0,1)
Global canvas=CreateCanvas(0,0,ClientWidth(window),ClientHeight(window),window)

Repeat
    Select WaitEvent(1)
        Case $803 : Exit
    
        Default
            SetBuffer CanvasBuffer(canvas)
            Cls
            DrawImage Toolbarimage,5,5,29
            FlipCanvas(canvas)

    End Select
Forever
End

The program breaks at the maskimage point and says invalid image handle.