hWnd [in]
    Type: HWND
    A handle to the window whose UIPI message filter is to be modified.
    message [in]
    Type: UINT
    The message that the message filter allows through or blocks.
    action [in]
    Type: DWORD
    The action to be performed, and can take one of the following values:
    Value	Meaning
    MSGFLT_ALLOW
    1
    Allows the message through the filter. This enables the message to be received by hWnd,
    regardless of the source of the message, even it comes from a lower privileged process.
    MSGFLT_DISALLOW
    2
    Blocks the message to be delivered to hWnd if it comes from a lower privileged process, 
    unless the message is allowed process-wide by using the ChangeWindowMessageFilter function or globally.
    MSGFLT_RESET
    0
    Resets the window message filter for hWnd to the default. Any message allowed globally
    or process-wide will get through, but any message not included in those two categories, 
    and which comes from a lower privileged process, will be blocked.
     
    pChangeFilterStruct [in, out, optional]
    Type: PCHANGEFILTERSTRUCT
    Optional pointer to a CHANGEFILTERSTRUCT structure.