Sub Conve_Forma_date()
Dim Derlign As Long
Derlign = ActiveSheet.Cells(Application.Rows.Count, 1).End(xlUp).Row
Range("B3").FormulaR1C1 = "=[@DATE]*1"
Range("B3:B" & Derlign).Copy
Range("A3").PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks:=False, Transpose:=False
Application.CutCopyMode = False
Columns("B:B").Delete Shift:=xlToLeft
Columns("A:A").NumberFormat = "m/d/yyyy"
End Sub