Actually I think the code would work better like this:- if ((msg.message >= WM_MOUSEFIRST) && (msg.message <= WM_MOUSELAST)) { mt.pt.x = (short)LOWORD(msg.lParam); mt.pt.y = (short)HIWORD(msg.lParam); ClientToScreen(msg.hwnd,&mt.pt); -----Original Message----- From: wine-patches-admin@xxxxxxxxxx [mailto:wine-patches-admin@xxxxxxxxxx] On Behalf Of Andrew de Quincey Sent: Friday, 5 December 2003 8:45 AM To: wine-patches Subject: menu: nasty bug in menu tracking In IDA, the menus don't work correctly... as you move down a menu, the wrong item is highlighted if you move to a submenu.. after that, the wrong menu is opened and other bad things occur. The problem is that MSG.lParam is NOT necessarily in screen coordinates (even though the comment I have removed says they are). As I can't trust the MSG.pt either, this means using GetCursorPos() to determine the mouse position in screen coordinates. BTW: MSDN says this about the MSG.lParam value for WM_MOUSEMOVED events: lParam The low-order word specifies the x-coordinate of the cursor. The coordinate is relative to the upper-left corner of the client area. The high-order word specifies the y-coordinate of the cursor. The coordinate is relative to the upper-left corner of the client area.