gistfile1.txt

Sub Macro1()
'
' Macro1 Macro
'

'
    Columns("E:E").Select
    Selection.Insert Shift:=xlToRight
    Range("E1").Select
    ActiveCell.FormulaR1C1 = "testing"
    Range("E2").Select
    ActiveCell.FormulaR1C1 = "=VLOOKUP(RC[-1],[testvlookup.xlsx]Sheet1!C1,1,0)"
    Range("E2").Select
    Selection.AutoFill Destination:=Range("E2:E746")
    Range("E2:E746").Select
    Selection.Copy
    Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
        :=False, Transpose:=False
    Range("E1").Select
    Application.CutCopyMode = False
End Sub