@alanbc

Adapte a função no seu código.

Public Declare Function GetKeyState Lib "user32" (ByVal nVirtKey As Long) As Integer

Function ISNUMLOCKkOn() As Boolean
    Dim Tmp As Long
    Tmp = GetKeyState(vbKeyNUMLOCK)
  If Tmp = 1 Then
    ISNUMLOCKkOn = True
  Else
    ISNUMLOCKkOn = False
  End If
End Function

olá... obrigado pela atenção.

consegui a solução:  https://stackoverflow.com/questions/25977933/sendkeys-is-messing-with-my-numlock-key-via-vba-code-in-access-form

Private Declare PtrSafe Function GetKeyState Lib "user32" (ByVal nVirtKey As Long) As Integer
Private Const kNumlock = 144

Public Function NumLock() As Boolean
NumLock = KeyState(kNumlock)
If (NumLock = False) Then
MsgBox "Numlock desligado. Ativado agora!"
SendKeys "{NUMLOCK}", True
Else: MsgBox "NumLock está ligado"
End If
End Function

Private Function KeyState(lKey As Long) As Boolean
KeyState = CBool(GetKeyState(lKey))
End Function

Sub...()

  Call NumLock

End Sub

Se é só pra manter ligado, sem ficar exibindo mensagens de texto, bastaria:

Public Declare Function GetKeyState Lib "user32" (ByVal nVirtKey As Long) As Integer
Sub LigaNumLock()
  If GetKeyState(VBA.vbKeyNumlock) <> 1 Then SendKeys "{NUMLOCK}", True
End Sub