Network TroubleShooting. Please help

[TheAmature]

i have just got comcast and already having problems, fuck comcast.
i have a laptop and a desktop, the desktop runs just fine, but the laptop doesn't receive and packets, only sends them.
i have no router so im using the same cable directly connected to the modem, so i know its not a cable problem

here is my laptops IPCONFIG when the ethernet is plugged in

[neuromanta]

It looks like your eth interface doesn't have az IPv4 address (only a "preferred" one, which is set by you I suppose), the router doesn't give an IP to your laptop using DHCP. See your router configuration, try to find out why it doesn't give an IP to the laptop. Also you could try to configure static IP for your laptop in your router (you know the MAC address of your eth interface).

[LuckY-BeanZ]

I am taking the assumption that you are using a home router, therefore i am again presuming it is both your default gateway and DNS server. Find the IP add of your router, statically assign that add as your default gateway and DNS as well as assigning the PC an IP within the same range, that should be an easy fix. As said above the preferred address is more than likely out of scope and in a different subnet to the router.

[74f100]

Your comcast modem uses MAC address filtering,,,,meaning it will only work with the MAC used when setting it up. You MUST have a router to connect 2 PC's to the modem.