Check if file exists

This macro display on column 'D' if file of columnd 'C' exists or does not exist:

Sub Macro1()
   Dim r As Long, lastRow As Long
   
   With ThisWorkbook.ActiveSheet
      'get last row
      lastRow = .Cells(Rows.Count, "c").End(xlUp).Row
      
      'cycle until last row
      For r = 2 To lastRow
         If Dir(.Cells(r, "c")) <> "" Then
            .Cells(r, "d") = "file exists"
         Else
            .Cells(r, "d") = "file doesn't exists"
         End If
      Next r
   End With
End Sub

Regards,
Antonio