You know when you start typing an email address into the To box in Outlook and a list of recipients appears?
Many people mistake those entries for people in their contact list, when in fact it is a list of remembered addresses that you have previously emailed. This list may be referred to as Autocomplete entries, Nicknames, Suggested Contacts, and more depending on who you talk to or which version of Outlook you’re using.
Sometimes this list contains addresses that you no longer want to appear, and deleting them is easy; simply using the arrow keys to highlight the address that you’d like to remove and press the Delete key. Or in newer versions of Outlook you can just mouse click on the X as visible in the screenshot above.