Advantages of Outlook AutoComplete

Microsoft Outlook has some nice productivity features for email addresses called AutoComplete. The auto complete feature displays a drop-down list of suggestions based on your typing when accessing any email address fields. It offers fast access, but sometimes the predictive text can suggest erroneous email addresses or interfere with how you work. Fortunately, you can correct wrong entries and also turn the feature off.

Before we begin, Microsoft has made some changes to address suggestions. If you’re using Outlook 2016 or older with a POP3 email account, you probably have an “NK2” file. This is a hidden file that is linked to a specific Outlook profile . This is sometimes called a nickname list or nickname cache. Don’t confuse this with the Nickname field on the Detail tab of a contact record.

Correcting Outlook Autocompletion Mistakes

It’s probably happened to all of us. In our rush to send an email, we enter the wrong email address. And these are often people not in our Contacts folder. The problem is the address will stay on this suggestion list until we fix

To correct Outlook nickname mistakes,

  1. Open an Untitled Message Window in Outlook.
  2. Type the first few letters so the wrong entry appears on the list.
  3. Highlight the item you wish to remove from the autosuggest list. You may need to use your directional keys to move up and down the list.
  4. Press your Delete key.
A bad email address appears in autocomplete.
Example of bad email
  1. Retype the correct entry in the address line and send the email.

When you close Outlook, your bad entry will be removed, and your corrected entry will be added.

How to Turn Off Auto Complete in Outlook

Some people find the auto-suggestions annoying. If these items are of concern, you can turn this suggestion feature off.

  1. From the File tab, select Options.
  2. On the Outlook Options dialog, click Mail.
  3. Scroll down to the Send messages section.
  4. Uncheck Use Auto-Complete List to suggest names.
  5. (Option) If you wish to delete the list, click the Empty Auto-Complete List button.
  6. Click the OK button.
Outlook mail settings panel.
Use Auto-Complete toggle

Tools to Read or Edit NK2 Files

Although some people are fearful of these files, they do offer benefits. If Outlook becomes corrupted, you may recreate contact records using the NK2 file as a source file. It won’t have all the contact details, but it’s a start. Or, if you’ve never created contacts and instead used AutoComplete to track your email addresses, the file is a good basis to build your Contacts. You can also copy the NK2 file to another computer.

One nice utility is from NirSoft because it also finds the Nk2 file location automatically. This can be an issue as the location and name change based on your Microsoft Outlook version and your operating system. The site also lists those file locations too.

AutoResolve Checks Email Addresses

AutoResolve is another convenience offered in Outlook but without concerns about hidden files. This feature checks the names you type on an outbound email to see if they match those in your Contact folder or address book. The intent is to prevent you from sending emails to people without email addresses or contacts with multiple email addresses.

In the example below, I typed Dorothy Gale, rather than clicking the Send New Message to Contact icon on her record or using the To button. When I click the Check Names button, Outlook will try to resolve Dorothy Gale’s name with the email addresses in my Contacts folder. In this example, Outlook is informing me that the name is not in my address book. I could create a new contact record.

Check Names dialog with no suggestions.
No suggestions for Dorothy Gale

This feature is also useful if you like to type partial names. In the example below, Check Names suggests John Hancock based on my typing John H. I can then choose one of the listed email addresses or find another record.

Outlook Check Names found 2 email addresses.
Multiple emails for John Hancock

Like AutoComplete, this feature is enabled from the same Outlook Options dialog. The option is called Automatic Name Checking.

As you can see, both AutoResolve and AutoComplete allow you to enter names or emails faster. You may find that one or both features serve your needs. The trick is knowing where the data comes from and how to act. However, if you’re prone to directly typing emails into the To: field and making typos, you may wish to turn off Outlook auto-complete.