I downgraded my ZP-NE14-S from V18.104.22.168 to V22.214.171.124 in order to view the video footage on my pc. It worked well for two months. However, I found out two days ago that the system upgraded itself back to V126.96.36.199 at 2am. I downgraded and the system upgraded around the same time again to V188.8.131.52.
How to prevent the system upgrading?