I currently have this macro:
Dim Lr As Long
Lr = Range("E" & Rows.Count).End(xlUp).Row
Range("P2").Select
Range("P2:P" & Lr).FormulaR1C1 = _
"=IF(VLOOKUP(RC[-9],'[IPNS Security 07092018.xlsx]Sheet1'!C8,1,FALSE),""ARGUS"")"
but the file name here the date "07092018"...