Hi there,

  It seems there is some problem with your DS6004HC devices. But I'm sorry we can not help since we can not make sure where and from whom you got these devices, I don't know who produced them.

  So I think the best way is to ask your provider for help, ask the one from whom you bought these devices, they have the duty to deal with the problem.

KillerLot:
I sent you a personal message, liu.

I replied personal message to you. Please check.

I can only judge if the devices are from us or not by checking with our sales, so you have to tell us where and from whom you get these devices, if not convenient for your to send in this forum, you can send personal message or email to support_eu@netvisiondvr.com