As posted earlier (the one that got us into this mess!). Does column 27 on nicely.

[vba]

'-----------------------------------------------------------------
Function ColumnLetter(Col As Long)
'-----------------------------------------------------------------
Dim sColumn As String
On Error Resume Next
sColumn = Split(Columns(Col).Address(, False), ":")(1)
On Error Goto 0
ColumnLetter = sColumn
End Function
[/vba]