We sell add kits for almost all versions of TiVo DVRs (as opposed to replace kits, which we do have for every single model). These add kits won’t install with version 6.4a of the DirecTV TiVo software on these models: Hughes HDVR2 Hughes SD-DVR40, SD-DVR80, SD-DVR120 RCA DVR39, DVR40, DVR80, and DVR120 DirecTV R10 All … Continue reading DirecTV TiVo OS Version 6.4a – Add Kits Fail