Since this is on the Comcast CableCARD thread, I will assume that you are on Comcast. FCC regulations require them to allow self-installs of CableCARDS and have since August 8th of last year. The process is not usually as smooth as it should be since Comcast has refused to adequately train their CSRs. What is the model # of your TiVo? If it is a Series 2, then it isn't HD nor does it support CableCARD. The other consideration is that the original Series 3 TiVo needs two CableCARDs.