Hi malefik,
"Undupe" means that you switch data deduplication off and return your files back to the state they were before the deduplication process.
Please, read the article it should help.
I had the same negative experience with Windows 2012 and Persona. And if I were you I'd thought about migration of your's Profile Server to the Windows 2008 Server. It works much stable.
P.S. Это англоязычная ветка, лучше отвечать на английском. Будет полезно для других при схожих проблемах