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Log into the NPI client application as an administrator.
Select System Configuration > > Settings.
Select the option you want to allow a specific user to be able to override.
Select the Add button button in the upper-right corner of the window (located just above the User and Value columns).
In the Option Information dialog, select the Add button, select a user, then select OK.
Select OK again to return to the Global Options tab.
On the right side of the window, you can now see that the user you selected can override the default value for that option.
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