NetworkService account access to a shared folder (WinSrv 2012R2)

Solution 1:

You need to use advanced sharing for this, go to
Properties
Sharing Tab
Advanced Sharing
Tick 'Share this Folder'
Click Permissions
Click Add
Click Object Types

The computer object will be shown in the list of available objects

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Solution 2:

you have to go to properties --> sharing --> advanced shareing. There you can choose the computer under the "object types".

But i would prevere to set the share to "everyone" and then change the rights over the NTFS-User rights. So you only have to manage the rights on one side...