All the examples I\'ve found refer to a class called ObjectContext, which doesn\'t appear to exist in CTP5. I must stress at this point, CTP5 is my first exposure to the Ent
I believe u do not need to attach the entity before u call modified. simply setting to modified will do the job.
if (_context.Entry(user).State == EntityState.Detached) { _context.Entry(user).State = EntityState.Modified; }