Offscreen DCs under Win2k Pro

I have this code, that worked on Windows 98 SE:

VB Code:

Public Function MakeDC(inW As Long, inH As Long) As Long
Dim lngDC As Long
 
    lngDC = CreateCompatibleDC(GetDC(GetDesktopWindow))
    If lngDC < 1 Then
        MakeDC = -1
        Exit Function
    End If
    SelectObject lngDC, CreateCompatibleBitmap(GetDC(GetDesktopWindow), inW, inH)
    
    MakeDC = lngDC
End Function

But now, 2 years later on Windows 2000 Professional, it doesn't. Any clues as to why? Pictures stored in the DC via. DrawIcon are never shown when the DC is blitted onto a picturebox's DC (which displays everything else fine).