The following made it easy to transfer that autocomplete data to a new profile.
You would create and log in with a new profile, let’s call it “Personal Email”. This would create a blank new NK2 file called “Personal Email.NK2″. Then you could simply delete that NK2 file (I usually renamed it to Personal Email.OLD” – force of habit). Next, rename “Work Email.NK2″ to “Personal Email.NK2″. When you log into your new profile all your auto-complete data was there.
This all changed in Outlook 2013. Outlook 2013 did away with the NK2 file completely and merged all the autocomplete data into the users Exchange Mailbox/PST file. This was great in part as many people often forgot to transfer that NK2 file when they moved to a new computer, or, the autocomplete data was lost in the event of a catastrophic failure, such as a failure of the local hard drive.
What I found is that in some form autocomplete data does still exist in your local profile. On a Windows 7 box if you navigate to the RoamCache folder identified below:
You may find one or more files called.
This is basically the new cache file for AutoComplete. The string of numbers is likely a SID of some form but where it is referenced (probably the registry) is beyond me.
All you need to do is identify what is the old autocomplete.dat file, normally by looking at the size of the file, the old one will be considerably bigger than the new one as it contains all of your cached addresses. Rename the old one to .old and copy the name before the .dat and rename your new one.