Why is a user's display name no longer displayed at the top right of the page?

For a certain Sharepoint 2010 site I have, all our users are Active Directory Users. For some of the users, when they log onto the site, it doesn't show their display name (Fistname and Surname) but rather the domain and username. For other users is fine. 开发者_C百科Does anyone know whay it would do this?

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Use Title instead of Name. Sounds backwards but Title is the main "column" and JobTitle is the job title.

Add this to your site URL to get an idea of what I mean. Hope this helps as you questions was a tad vague.

/_layouts/userdisp.aspx?Force=true

Good Luck