Remove individual addresses from the autocompletion cache by highlighting
the entry when presented in the suggested names list (use your arrow key to
migrate to the entry) and then hitting your Delete key before you tab out of
the field. To clear the entire cache, follow the instructions here:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q287623

John,

Russ' advice works well for the occasional deletion of an unwanted e-mail
address.  However, often you don't even know that an address is incorrect,
especially if it is stored in your autocomplete cache two different ways.
If you're interested, you can review a demo version of a utility that we
developed that will allow you to view the entire contects of the NK2 file.

It can be found at www.dcs-imaging.com/products.htm.

Good luck!
Randy