If your cameras do not appear immediately after the reboot, you may need to re-pair them. Since the firmware update sometimes resets the wireless configuration, go to the "Video Manage" screen and use the "Match Code" function. Connect each camera to the NVR via an Ethernet cable for 30 seconds to sync the new security protocols, then return them to their wireless locations. If the NVR stuck on the logo screen, you may need to perform a hard reset or attempt a recovery flash using a specialized TFTP tool, though this is an advanced procedure.