You can certainly look at Outlook data programmatically and I don't see why
you couldn't then use it to populate a combo box or use it for validation.
You'll need either an Outlook object or a MAPI object - there should be some
pages of help on it if you search Microsoft.com or Google (sorry I've got
nothing to hand at present but I've certainly done similar things in the
past).

"Ed" wrote:

Is there any way I can link the data validation in a column of cells in an
Excel worksheet to my default Outlook contacts list? I'm trying to set up a
workbook for another user, and I'd like to make it easier for him to insert
the email address of the person listed. I thought a data validation linked
to the contacts list would give him a drop down menu, rather than hope he
types it in correctly.

If that doesn't work, is there a way I can check a name from the worksheet
against the contacts list to return the email address?

Thanks.
Ed