How to change user account picture

In Server 2012, similar to Server 2008 R2; the 'Desktop Experience' feature is required to achieve the similar interface experience as Win7/8. This feature can be added from the Server Manager, under 'User Interfaces and Infrastructure.' Once added, either Win+I to Change PC Settings/Personalize/Account Picture, or from the Metro Start screen, click the username charm in the upper right corner, select change account picture.

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