| Microsoft Outlook Contacts AutoComplete Format | |
| Microsoft | |
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NK2 is an extension characteristic of the popular Microsoft e-mail client, Outlook. NK2 file collects data used in the autocomplete content written by the user manually (e.g. e-mail addresses or popular phrases). Such a file also contains a defined nickname associated with the program's user profile and his e-mail address.
Until 2002, files fulfilling this role had the NICK extension. NK2 files are usually hidden in the system.
Windows
Updated 02/10/2022
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