How to upgrade DVR System? jeremy October 27, 2018 04:08 Updated Follow How to upgrade DVR System? Related articles 08HA V1.1.6 Upgrade file -- AHD, 720P, 3521a how to setup your ZOSI DVR system with ZOSI view app? 08HA V1.1.5 Upgrade file_AHD, 720P, 3521a DVR System: how to install and format the hard drive? 04PN V1.2.1 Upgrade file -- rootfs-3520dv300, TVI, 1080P Comments 0 comments Please sign in to leave a comment.