HI,
The data validation below works on MS Excel 2002 on a PC.
ie. a list of names is displayed in a drop down box.
But on Mac Excel the drop down list is empty.

Data Validation
Allow: List
Source:
=OFFSET(INDIRECT("[Tracker.xls]Roster!dbROSTERname"),0,0,COUNTA(INDIRECT("[Tracker.xls]Roster!dbROSTERname")),1)

where
dbROSTERname
=Roster!$D$7:$D$1223