derekheld

Personal Library allows you to restrict users to seeing their own media uploads. The plugin works by filtering all requests for attachments.
<ul>
<li>Administrators will always see all attachments</li>
<li>Enable or disable access to all uploads for the following roles: contributor, author, editor.</li>
</ul>

Personal Library

Restricts users to managing/using their own attachments only.

nafsadh

Validate Profile Credentials and Names
In a WordPress site users have multiple names in their profile, the user login, display name and nick name. In a multi-user site, there is often a need to keep them unique. You need to allow users have only credible names, such that,
<ul>
<li>All display names are unique</li>
<li>All nicknames are unique</li>
<li>No nickname is a display name or login name of another user</li>
<li>No display name is a nickname or login name of another user</li>
</ul>
Credible Names is a easy plugin to help you with that.

Credible Names

Ensure user's nickname and display name are unique and not a display name or nick name or user name of someone else

Personal Library vs Credible Names