This atricle describes how to move the names cache file from one PC to another. This file is what autofills the email addresses into the “to” line as you type. It is not part of the .pst file in any version of Outlook older than 2010.
In Windows XP
1. On the new PC send one test message and close Outlook
2. Copy the .nk2 file from the old PC
For XP hit start and run and type %userprofile%application dataMicrosoftoutlook
For Vista or XP his start and run and type %userprofile%appdataroamingMicrosoftoutlook
3.In the above folder you will see the .nk2 file
Typically this file is called outlook.nk2 but if your profile in outlook is named something other
than outlook it will be named that profile name
4.Copy this file to the same location on the new PC if it is XP or to if it is Windows 7 %ueserprofile%appdataRoamingMicrosoftOutlook overwriting the file in that folder.
Again typically this file is called outlook.nk2 but if your original file is name something other
than outlook.nk2 you will need to rename it to match the file on the new PC, say yes to
overwrite the existing file.
**anything in the new file will be lost but that is usually Ok since it would be mostly blank**
5. Open outlook on the new PC and test that this is working by hitting a key on the keyboard, I usually use “a” to see if it auto fills in any email addresses, probably don’t use the z key since it’s not a very common email address starter.
6.All should be well but if not reproduce the above steps and try again.
7.If you are moving from an older version of outlook to a Outlook 2010 click the following link for detailed instructions on how to import the .nk2 file into your new Outlook 2010 profile.