i got some help yesterday from some of you good people on
building a macro that would allow me to use a function
i've built to pull last names from full names. i'd like
the macro to insert a new column and use my function to
fill that new column with the last names of all the full
names in the first column.

i'm getting an error when i try to run this macro.

here it is:

Sub Macro1()

Dim iRow As Long
Dim rng As Range
Columns("B:B").Insert Shift:=xlToRight
Range("B1").FormulaR1C1 = "=PERSONAL.xls!getlastname(RC
[-1])"
With ActiveSheet
iRow = .Range("A" & Rows.Count).End(x1Up).Row
Set rng = .Range("B2:B" & iRow)
rng.FormulaR1C1 = "PERSONAL.xls!getlastname(RC[-1])"
End With

End Sub

after i run it, there is a new column inserted, and the
top record has the last name pulled out of the full name
and inserted into the new column.......and then the
error. the remainder of the column is empty.

the error states:

run time error '1004':

Application-defined or object-defined error

any ideas? thanks.