Why does SendInput Ctrl+V not work in Outlook?

Question

I have a program that uses system wide hotkeys Ctrl+Shift+a key of the user's choice to paste the text in the clipboard by sending the Ctrl+V combination using SendInput as used here. This works fine in most programs. But in Outlook on the To field of a new email, every key I try ends up bringing up the "Move Item To Folder" Outlook dialog box which is supposed to be the Ctrl+Shift+V key combination. In the Body field nothing happens. Any ideas what is happening here? See code to reproduce below:

procedure TForm1.FormCreate(Sender: TObject);
begin
  If not RegisterHotkey( Handle, 1, MOD_SHIFT or  MOD_CONTROL, Ord('P') ) Then
    ShowMessage('Error');
end;

Procedure TForm1.WMHotkey( Var msg: TWMHotkey );
var
  KeyInputs: array of TInput;

  procedure KeybdInput(VKey: Byte; Flags: DWORD);
  begin
    SetLength(KeyInputs, Length(KeyInputs)+1);
    KeyInputs[high(KeyInputs)].Itype := INPUT_KEYBOARD;
    with  KeyInputs[high(KeyInputs)].ki do
    begin
      wVk := VKey;
      wScan := MapVirtualKey(wVk, 0);
      dwFlags := Flags;
    end;
  end;

Begin
  If (msg.HotKey > 0) And (msg.HotKey < 2) Then
  Begin
    Clipboard.AsText:= 'Some text';
    KeybdInput(VK_CONTROL, 0);                // Ctrl
    KeybdInput(Ord('V'), 0);
    KeybdInput(Ord('V'), KEYEVENTF_KEYUP);
    KeybdInput(VK_CONTROL, KEYEVENTF_KEYUP); // Ctrl
    SendInput(Length(KeyInputs), KeyInputs[0], SizeOf(KeyInputs[0]));
  end
End;

Answer 1

SendInput does not reset the current state of the keyboard. So Outlook sees the Ctrl+Shift of your Hotkey. You have to simulate releasing the Shift key.

So if I do the following, it works in Outlook:

var
  input: TInput;
begin
  // This releases the shift Key:
  input.Itype := INPUT_KEYBOARD;
  input.ki.wVk := VK_SHIFT;
  input.ki.wScan := 0;
  input.ki.dwFlags := KEYEVENTF_KEYUP;
  input.ki.time := 0;
  input.ki.dwExtraInfo := 0;
  SendInput(1, input, sizeof(input));

  // Send 'V'
  input.Itype := INPUT_KEYBOARD;
  input.ki.wVk := Ord('V');
  input.ki.wScan := Ord('V');
  input.ki.dwFlags := 0;
  input.ki.time := 0;
  input.ki.dwExtraInfo := 0;
  SendInput(1, input, sizeof(input));
  input.ki.dwFlags := KEYEVENTF_KEYUP;
  SendInput(1, input, sizeof(input));
end;