With Outlook 2010+ on Exchange 2010+ NK2 files are deprecated and replaced with server side(ish) secret listings.
To export 2007 NK2’s seamlessly:
1. copy .nk2 file from user dir (in XP that’s “%USERPROFILE%Application DataMicrosoftOutlook*.nk2”
2. create the new directory “%appdata%MicrosoftOutlook” on the recipient machine
3, drop the copied nk2 in (assuming it’s named Outlook.nk2
4. Setup Outlook 2010 on new PC using the Outlook profile (or match name to nk2 name or vice versa)
5. the nk2 is then imported into the users 2010 profile on the server and renamed .file!