Kod:
Sub cevir()
son = Range("A" & Rows.Count).End(3).Row
For i = 3 To son
zaman = Range("B" & i).Value
If Right(zaman, 7) = "MERKEZİ" Then
Range("h" & i).Value = zaman
Else
Range("h" & i).Value = Application.Substitute(Application.Substitute(Application.Substitute(zaman, ".", ":"), ":", ".", 3), "000000", "")
Range("h" & i).NumberFormat = "dd.mm.yyyy hh:mm:ss.000"
End If
Next
End Sub