Roamio unable to see content of another Tivo

Hi,

I am upgrading to a Roamio and have a lot of recordings on the old Tivo XL4. I see the XL4 on the list of devices from the Roamio, but when I attempt to see it's recordings I get a network error message. Any ideas why?

Perhaps I need a cable card in the Roamio to see the Comcast content?