 If FindWindow fails to find the MSWHEEL
'// window or the return from SendMessage is false, then Wheel support
'// is not currently available.
Private Const MSH_WHEELSUPPORT = "MSH_WHEELSUPPORT_MSG"
Private Const MSH_SCROLL_LINES = "MSH_SCROLL_LINES_MSG"

' Flat scroll bars:
Private Const WSB_PROP_CYVSCROLL = &amp;H1&amp;
Private Const WSB_PROP_CXHSCROLL = &amp;H2&amp;
Private Const WSB_PROP_CYHSCROLL = &amp;H4&amp;
Private Const WSB_PROP_CXVSCROLL = &amp;H8&amp;
Private Const WSB_PROP_CXHTHUMB = &amp;H10&