Did you also transfer his c:\notes\notes.ini from the old PC to the new one? I assume you did, but want to make sure.
To clarify the previous person’s answer — The notes.ini on the machine points to the data directory. There’s an entry of “Data Directory=”. That is where the names.nsf file must reside. If you put the “old” names.nsf in some place other than what is listed there, Notes will create a new names.nsf and use it. You can simply put the old names.nsf in place and going forward, it should be fine.