The .NK2 file used by Outlook 2003 and Outlook 2007 and is used to suggest addresses when you start typing in the recipients field is no longer used by Outlook 2010.
This file can be imported by Outlook 2010 and the contacts placed in the "Suggested Contacts" folder in the mailbox.
Copy the .NK2 file to the "C:\Users\%username%\AppDa
Rename the nk2-file to the name of your mail profile:
In the Control Panel, type "mail" into the search box.
Run the Mail applet.
Click on the Show Profiles… button.
By default, your profile is called “Outlook”. So in that case you would call your file “outlook.nk2”.
Run the Mail applet.
Click on the Show Profiles… button.
By default, your profile is called “Outlook”. So in that case you would call your file “outlook.nk2”.
Start Outlook with the /importnk2 switch:
outlook.exe /importnk2
Outlook will import the NK2 data into the Suggested Contacts folder.