No. Versions of Outlook earlier than Outlook 2002 have no autocompletion
feature. They have a feature called auto-resolution. If you enter part of a
name or a nickname then tab out of the field (or hit Alt-K [Check Names]),
Outlook will attempt to resolve the name against your address book. If it
can't it'll red underline it and you can right click on the name to manually
resolve it. Outlook will save the resolution for future use.
