Channel Unavailable

We've just made the switch to Time Warner Cable (TWC) in Los Angeles. When searching through the channels we receive, I get a message on the screen from TiVo saying "Channel is temporarily unavailable...". While this message is on screen there is also blue bar on the top of the screen showing the name of the channel and the channel number as Tivo would do for any channel.

This occurs with several channels.

What's happening and what can I do about it?

Thanks;

Stan