Would suggest you convert them to Excel dates. The following
macro will convert a text string of numbers or a number of 8 digits
to Excel date format. The the formatting will match the short date
format in your regional settings (control panel).

Sub Fixmmddyyyy()
Dim cell As Range
Selection.NumberFormat = "mm/dd/yyyy"
On Error Resume Next
For Each cell In Selection
If Len(cell) = 8 Then
cell.Value = DateSerial(Right(cell.Value, 4), _
Left(cell.Value, 2), Mid(cell.Value, 3, 2))
End If
Next cell
End Sub

Test on a copy of your worksheet. Should be safe to reuse
on a column that is already converted because the length will
no longer be 8.

If not familiar with installing and using macros see
http://www.mvps.org/dmcritchie/excel/getstarted.htm

More information on Date and Time in
http://www.mvps.org/dmcritchie/excel/datetime.htm
---
HTH,
David McRitchie, Microsoft MVP - Excel [site changed Nov. 2001]
My Excel Pages: http://www.mvps.org/dmcritchie/excel/excel.htm
Search Page: http://www.mvps.org/dmcritchie/excel/search.htm

"DraCo" wrote in message ...
How do I insert a seperator (/) into a number string (20050822) to format a
date column? This number string is brought in from an outside source and
cannot be manipulated by the program (AccPac) generating the string.