Advertisements With TiVo since 1999. My Roamio OTA hard drive failed and I put in a working 500 GB I had handy. When I setup, a large pink window came up and advised me to call Tivo because I was downgrading software. Is this because the Roamio OTA can only operate with a 1 TB or larger drive. I thought these Roamio hard drives were interchangeable, in a pinch. I have several larger TiVo’s but use this for news shows that I delete and I like having an empty MY SHOWS folder on this TiVo. Do I need to buy a 1 TB or can TiVo Technical Support help me get the 500 GB to work. Thanks.