How to import .nk2 files into Outlook 2010

When you start Microsoft Outlook 2010 for the first time, your nickname cache (stored in the profilename.nk2 file) is imported into a hidden message in your default message store.

Note profilename is the name of your Outlook profile.

For example, if you are using a Microsoft Exchange account, the nickname cache is imported into a hidden message in the Exchange mailbox.

Note Earlier versions of Outlook store the nickname cache .nk2 file in the following folder.
  • Windows XP
    Drive:\Documents and Settings\Username\Application Data\Microsoft\Outlook
  • Windows Vista and later versions
After the nickname cache is imported, the profilename.nk2 file is renamed to profilename.nk2.old. On the next start of Outlook, your nickname cache is not imported. Outlook 2010 does not use the .nk2 file for maintaining your nickname cache. All updates to your nickname cache in Outlook 2010 are made to the hidden message in your default message store.

Note If you have multiple Outlook profiles, the nickname cache from each profile is merged into your new Outlook 2010 nickname cache on the first start of Outlook 2010 by using that profile. Therefore, you may find more than one .nk2 file renamed to .nk2.old.

However, there may be situations where you have to import a nickname cache file after this first-run nickname cache import process has finished. For example, a colleague wants to share their nickname cache with you and you want to update your existing nickname cache with your colleague’s data.

This article discusses how to import .nk2 files into Outlook 2010.
More information
To have us import .nk2 files for you, go to the "Here's an easy fix" section. If you prefer to import .nk2 files yourself, go to the "Let me fix it myself" section.

Here's an easy fix

To fix this problem automatically, click the Download button. In the File Download dialog box, click Run or Open, and then follow the steps in the easy fix wizard.
  • Please select an .nk2 file that you want to import into Outlook 2010.
  • This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
  • If you’re not on the computer that has the problem, save the easy fix solution to a flash drive or a CD, and then run it on the computer that has the problem.

Let me fix it myself

Easy fix 50584

To import .nk2 files into Outlook 2010, follow these steps:  
  1. Make sure that the .nk2 file is in the following folder:
    Note The .nk2 file must have the same name as your current Outlook 2010 profile. By default, the profile name is "Outlook." To check the profile name, follow these steps:
    1. Click Start, and then click Control Panel.
    2. Double-click Mail.
    3. In the Mail Setup dialog box, click Show Profiles.
  2. Click Start, and then click Run.
  3. In the Open box, type outlook.exe /importnk2, and then click OK. This should import the .nk2 file into the Outlook 2010 profile.

    Note After you import the .nk2 file, the contents of the file are merged into the existing nickname cache that is currently stored in your mailbox.
Note The .nk2 file is renamed with a .old file name extension on the first start of Outlook 2010. Therefore, if you try to re-import the .nk2 file, remove the .old file name extension.

Video: How to import .nk2 files into Outlook 2010

Did this fix the problem?

Check whether the problem is fixed. If the problem is fixed, you are finished with this section. If the problem is not fixed, you can contact support.
For more information, visit the following Microsoft Web sites:
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
287623 How to reset the nickname and the automatic completion caches in Outlook
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Article ID: 980542 - Last Review: 09/28/2015 08:48:00 - Revision: 19.0

  • Microsoft Outlook 2010
  • kbtshoot kbexpertisebeginner kbsurveynew kbprb kbfixme kbmsifixme kbvideocontent KB980542