I'm having a problem trying to get Set = to allow a split range.

I'll explain. I have a custom function that allows you to get data from
another Workbook, one of the lines of code is this...

Set r = xlwb.Sheets(1).Range(Mid(xref, n + 1))

r is a Range variable. this is my problem variable.
xlwb is a Workbook variable that has already been set and is working fine.
xref is a string which contains (among other things) the range we want.
n is a variable which denotes where to find the range in xref. Again this is
fine.

I get a problem when I the Range(Mid(xref, n + 1)) evaluates to this...

Range(("A1:A10, C1:C10"))

I'm not sure if the syntax is wrong as I'm using the Set command or what.

Any help would be gratefully received.

TIA.