参考答案

Private Sub C1_Click()
    Dim n As Integer, k As Integer, s As Long
    n = Val(Cb1.Text)
    s = 0
    For k = n To 5000
        If k / n = Int(k / n) Then
            s = s + k
        End If
    Next k
    Text1.Text = s
End Sub
Private Sub Form_Unload(Cancel As Integer)
    unload_sub
End Sub