public void Update(sysBpmsThreadEvent threadEvent) { //To fix 'Attaching an entity failed' error. var local = this.Context.Set <sysBpmsThreadEvent>().Local.FirstOrDefault(f => f.ID == threadEvent.ID); if (local != null) { this.Context.Entry(local).State = EntityState.Detached; local = null; } this.Context.Entry(threadEvent.Clone()).State = EntityState.Modified; }