uint nMsg = RegisterWindowMessage("WM_HTML_GETOBJECT");

///     The <see cref="RegisterWindowMessage" /> function is typically used to register messages for communicating between

///     <see cref="RegisterWindowMessage" /> when more than one application must process the same message.For sending

/// static extern uint RegisterWindowMessage(string lpString);

///      queryCancelAutoPlay = RegisterWindowMessage("QueryCancelAutoPlay");

static extern uint RegisterWindowMessage(string lpString);

Private Shared Function RegisterWindowMessage( _

class method RegisterWindowMessage(lpString: String): UInt32; external;

Declare Function RegisterWindowMessage Lib "user32.dll" (ByVal lpString As String) As Integer

    DllImport("user32.dll", EntryPoint = "RegisterWindowMessageW", SetLastError = true)]

    private static extern int RegisterWindowMessage(string lpString);

Declare Function RegisterWindowMessage Lib "user32.dll" Alias "RegisterWindowMessageW" (ByVal lpString As long) As Integer

    lngWindowMsg = RegisterWindowMessage(StrPtr(strMessageToRegister))

If you use RegisterWindowMessage("QueryCancelAutoPlay") it will NOT work, put the "QueryCancelAutoPlay" in a variable or constant and use that one.

    MessageID = RegisterWindowMessage("QueryCancelAutoPlay")

lMsg = Win32.RegisterWindowMessage("WM_HTML_GETOBJECT");

static extern uint RegisterWindowMessage(string lpString);

        queryCancelAutoPlay = RegisterWindowMessage("QueryCancelAutoPlay");

lMsg = Win32.RegisterWindowMessage("WM_HTML_GETOBJECT");

lMsg = Win32.RegisterWindowMessage("WM_HTML_GETOBJECT");

    Private Shared Function RegisterWindowMessage(ByVal msg As String) As Integer

    uCallbackMessage = RegisterWindowMessage("AppBarMessage")