When entering the first or second letter of an e-mail address in a new e-mail using outlook you are presented with some e-mail addresses that start with these letters. You can then select the correct one, click on it and it enters the address line

My question is where are these addresses stored, so that I can delete an incorrect one and replace it with the correct address

Or how can I search for them?

They are not in the Outlook Address book or contacts list

Many thanks

The absolute simplest way is to start typing until the wrong one shows up in the choices that start with what you are typing, hit down until you get to the incorrect one and then just hit delete while it is still selected in the drop down window(don't click on it just scroll down to it and hit delete on the keyboard). That will remove the incorrect address from your suggested contacts list. If that doesn't work then you may have to wipe the whole file.
Follow this for step by step instructions on wiping the whole file but definately try the above option first.
http://support.microsoft.com/?kbid=287623

SCBARTON
Many thanks for your prompt reply the easy suggestion worked well