Мне удалось сделать следующее:
HWND HMyTooltip = NULL, HNew = FindWindow( "tooltips_class32", NULL );
// Cycle through all visible tooltip windows looking for the one we want
while (HNew && !HMyTooltip)
{
if (IsWindowVisible(HNew))
{
HMyTooltip = HNew;
// If you want to find a particular tooltip, check the text (Note: GetWindowText doesn't work)
SendMessage( HMyTooltip, WM_GETTEXT, ARRAYSIZE(Title), (LPARAM)Title );
if (_strnicmp( Title, "USB Device Not Recognised", 22 ) != 0)
HMyTooltip = NULL;
}
HNew = GetWindow( HNew, GW_HWNDNEXT );
}