Is this Outlook 2002 or 2003? If so, the bad autocomplete entry is located
in your autocomplete cache file. If you want to delete individual entries
from this file, start typing in a name and when the list comes up, point to
the entry you want to delete (so that it's highlighted) and press Delete.
To delete the whole cache and start over, look for a file with an .NK2
extension and rename it or move it. Outlook will start a new cache file the
next time an e-mail address is typed into the To: box. Note that if you're
using Windows 2000 or XP, you'll need to search in hidden and system folders
to find the .NK2 file (it also helps to have file extensions visible).

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Jocelyn Fiorello
MVP - Outlook
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> Each time I send an email one particular person - the
> properties on the address are an old email address that is
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>
> Can anyone tell me where outlook is getting this address?