Yes, it actually needs to be decrypted. Use TivoDecode (free). You do not need it if the computer has Tivo Desktop installed ($15).
Series 2 (80 hrs,PLS, Retired)
TiVo HD 1TB (157 HD Hrs, PLS, "S3HD")
Roamio, Oh Roamio!
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!