Need to open TCP ports for TiVo Bolt and TiVo Mini access via ethernet

Recently replaced an old Motorola surfboard modem with NetGear CM600.  Cable & internet provided by Cox runs from street to panel in my house with modem in panel; ethernet from modem runs to switch which in turn sends internet through proper house wiring to jacks in various rooms.  All worked fine before switching modems.  Everything else works fine with new modem except TiVo.  Every wired ethernet jack has been tested and works properly.  All new cabling.  All tests show everything works except the TCP port error in TiVo.

 

TiVo Bolt and Minis require hard line ethernet connectivity.  Since modem change, I get an IP address, but I'm getting no DNS assignment when connecting TiVo.  Bolt error message says TCP failure requires the following ports to be opened:  TCP port 37, 80, 7288, 7287, 8080, 8081, and 5223.  Cox says 80 is blocked by them for security purposes but all others should be OK for me to open.  Tried talking to TiVo support, Cox support and NetGear support.  None can direct me to anywhere that I can get to even see whether these ports are open or not.  I don't understand why they wouldn't be already set properly.  I haven't changed any settings from factory defaults in my firmware or in my firewall.  If it worked before this modem, I don't understand why it won't work now.

 

How do I get to into the settings to a) determine if these TCP ports are open or not, and b) fix them.  All the community forum posts with links don't go anywhere (just error to blank screens).

 

Help.  Please.  I just want to watch TV over my TiVo system again.