You did not mention what model Tivo you have and how things are connected.
You might try to restart by pulling the power cord, otherwise there is not enough info to help.
Series 2 (Retired, sold)
TiVo HD 1TB (157 HD Hrs, PLS, "S3HD")
Roamio, Oh Roamio!
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!