This article will explain the steps necessary to import a .nk2 file with Outlook 2010.
1. Close Outlook 2010.
2. Make sure the legacy.nk2 file is in the following folder: %appdata%MicrosoftOutlook
Note: To jump to this directory, click Start > Run. Copy and Paste the following command into the Run dialog address bar then click OK: %HOMEPATH%Application DataMicrosoftOutlook
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, click Start > Control Panel > Mail > Show Profiles
3. Click Start > Run. Copy and Paste the following command in the Run dialog address bar then click OK: outlook.exe /importnk2
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. if you try to re-import the .nk2 file, remove the .old file name extension.