On Thu, 23 May 2013 12:59:14 +0100, _Adrian wrote:

I wondered if the regional settings would make a difference within
Excel, but his Excel Help for the TEXT function still shows ddd as being
valid. I'll ask about his settings.
Thanks.

If the problem is a regional settings issue, and the user does not wish to change is regional settings, you could use an xl4 macro to return the proper code.

You cannot use xl4 macro formulas directly in a worksheet, but you can use them as a Defined Name:

Formulas/Define Name
Name: DayCode
Refers to: =INDEX(GET.WORKSPACE(37),21)

Then, in the worksheet, use:

=TEXT(A1,REPT(DayCode,3))

This should work with any country setting.