Remove addresses from AutoSuggest/Auto-Complete

When typing an address in the “To:” line I get a list of addresses to choose from. There are several of these autocomplete recipient names in there which I’ve mistyped and also some that I don’t use anymore.

How can I remove these? They are not in my Contacts folder either. Where are they?

The AutoSuggest/Auto-Complete feature of Outlook keeps a cache of addresses you’ve recently used. It is not related to the default Contacts folder. Instead, they are kept in a special cache location.

Removing a single address

When addressing an email and a name you want to remove pops-up, use your arrow keys on your keyboard to select it and press Delete.

In Outlook 2010 and Outlook 2013, you can also click on the X icon on the right side of the selected list item to delete it from the suggestion list (but not from the Suggested Contacts folder).

Another method, in Outlook 2010, is to remove the contact item from the Suggested Contacts folder. To see all your Contact folders, switch to the Contacts Navigation (keyboard shortcut: CTRL+3).

Deleting an address from the Auto-Complete list in Outlook 2010
How to delete a suggested address is much more obvious in Outlook 2010.

Disable AutoSuggest or Auto-Complete

To disable this suggestion feature completely;

  • Outlook 2007 and previous
    Tools-> Options-> button E-mail Options…-> Advanced E-mail Options…-> deselect: Suggest names while completing To, Cc, and Bcc fields
  • Outlook 2010 and Outlook 2013
    File-> Options-> section Mail-> option group: Send messages-> deselect: Use Auto-Complete List to suggest names when typing in the To, CC and Bcc lines

Remove all addresses from the AutoSuggest/Auto-Complete list

If you want to reset the AutoSuggest/Auto-Complete list to remove all addresses at once, the method to do so depends on your version of Outlook.

Outlook 2007 and previous
The addresses are kept in a separate cache file with the nk2 extension. By renaming the file to .old while Outlook is closed the entire AutoSuggest list will be reset.

This file can be found .and can be found in the following location;

  • Windows XP
    C:\Documents and Settings\%username%\Application Data\Microsoft\Outlook\
  • Windows Vista, Windows 7 and Windows 8

Outlook 2010 and Outlook 2013
In Outlook 2010 and Outlook 2013 the Auto-Complete list is kept in a special hidden message in your mailbox. Resetting the list can be done in the following ways;

  • Empty the Suggested Contacts folder (only applies to Outlook 2010)
    The contacts in the Suggested Contacts folder hold a relation to the Auto-Complete list. Delete a contact from this folder and it will also be removed from the Auto-Complete list.
  • Button: Empty Auto-Complete List
    Using the “Empty Auto-Complete List” button does exactly what is says. When using this option the contacts in the Suggested Contacts folder will not be deleted.
    You can find the option here;
    File-> Options-> section Mail-> option group: Send messages-> button: Empty Auto-Complete List
  • Startup switch: cleanautocompletecache
    By starting Outlook with the cleanautocompletecache startup switch you’ll achieve the exact same results as using the button “Empty Auto-Complete List.
    You can execute this switch in the following way (note the space in the command);
    • Windows XP
      Start-> Run-> outlook.exe /cleanautocompletecache
    • Windows Vista, Windows 7 and Windows 8
      Start-> type; outlook.exe /cleanautocompletecache