Originally Posted by lillevig
Did you set up a static IP for your S2? Sometimes that works when DHCP doesn't.
This is what I'm guessing. Your new router may have used a different IP address (i.e., default gateway) than your old one (192.168.1.1 vs. 192.168.0.1 or vice versa), resulting in completely different IP addresses being assigned via HDCP. Any device that was set up with a static IP with the old router will no longer be recognized by the new router. Go into your network settings and change from a static IP to DHCP and reboot the Tivo. The Tivo will be assigned a new IP address by the router that your PC can recognize. You can then go into your Tivo's network settings and reassign a new static IP address based on the new default gateway (i.e., your router's IP address).
Edit: I just realized you have a series 2 Tivo and probably don't have the ability top configure a static IP via the network settings menu. If you do have a static IP then you probably hacked the unit to set it up. You'll have to change the static IP address to match the router's default gateway setting using whatever method you used to hack it in the first place. I haven't hacked a Tivo in years so I don't recall the file that needs to be modified, although I suspect it's the rc.sysinit file.