I once sent one message to a David Something. Now, every
time I try to address an email to a David with whom I
regularly correspond Outlook offers David Something's
email address as the first likely fill in. Is there
somewhere I can clear a cache to lose that address
forever?

You failed to post your Outlook version.
Assuming Outlook 2002 or 2003, 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...;EN-US;Q287623


--
Russ Valentine
[MVP-Outlook]
"Michael" <(E-Mail Removed)> wrote in message
news:14b9b01c445a0$b7c0db50$(E-Mail Removed)...
> I once sent one message to a David Something. Now, every
> time I try to address an email to a David with whom I
> regularly correspond Outlook offers David Something's
> email address as the first likely fill in. Is there
> somewhere I can clear a cache to lose that address
> forever?