Your NVR will save recordings as 3 possible file types: .mp4, .dav, .asf, .mp4 is playable by almost all video playing apps & programs. .dav and .asf are less commonly supported, Watchnet offers programs for playing these files:
For Windows:
http://watchnetlink.com/Downloads/Embedded/Software/smartplayer/QuickSmartPlayer_20140428.zip
For Mac:
http://watchnetlink.com/Downloads/Embedded/Software/MAC_quick_player.zip
