Outlook 2016 nk2 file not updating
In Outlook 2007, the autocomplete list is stored in a file with the extension NK2.If you are moving from Outlook 2003 or 2007, you'll need to import the NK2.The auto-complete list for Outlook 2010 and above is stored in files in the Roam Cache folder under the Local App Data folders.You can access this folder by typing or pasting the following command into the address bar of Windows Explorer and pressing enter.Microsoft Outlook keeps a list of recently used email addresses that you typed in the To, Cc, and Bcc fields of an email message.Back up or copy that file elsewhere if you want to keep the list or use it on a different computer.The Auto Complete information of Outlook is stored inside a special file with .nk2 extension (on Outlook 2010 it's extension).When Outlook Auto Complete is not working, it means that this .nk2 file is probably corrupted, and Outlook fails to read it.
To set the root folder path for your IMAP account: File- Account Settings…
If I do a search for an email which I have seen on another of my devices, it will find it and I am able to send emails.
However, the Inbox is not updating to include current emails.
An example of an add-in which has caused a lot of issues is the “Outlook Change Notifier”. Note that this is just an example; other add-ins can cause the same issues as well.
When installing i Tunes, it also installs an Outlook add-in called Outlook Change Notifier.