I have a client that is using Outlook 2007 and the auto-complete feature that fills in the to field in a new email has become sporadic. It's as if the entire cache got wiped and is being repopulated. I know that Outlook 2003 uses a .NK2 file which you can backup and reuse as needed, however, Outlook 2007 doesn't appear to work the same way. Anyone know of a way to backup the auto-complete information and restore it? At this point the only information I've heard is that a reboot allows you to start repopulating the information again, but it'd be nice to have a way to prevent the loss of this information.