Hello,
I install Linksys routers all the time. Usually the first thing I do, is update the routers firmware. Many times I find that if the Linksys router doesn't automatically get a connection from DHCP, updating the firmware usually solves it.
To update the firmware:
Connect just to the cable box so you have an active internet connection.
1. Go to:
http://homesupport.cisco.com/en-us/wireless/lbc/WRT54G2/download2. Select your router version (can be found on the sticker near the model number) and download the latest firmware to a spot you will remember.
3. Now connect the router to your cable modem and computer.
4. Access your routers configuration page (If you don't know the address try:
http://192.168.1.1 or
http://192.168.0.1).
5. Log-in - if you haven't changed the username/password the default should be a blank username with the password "admin".
6. Click "Administration"
7. Click "Firmware Upgrade"
8. Click "Browse" and choose the firmware file you downloaded in step 2.
10. Click Upgrade. Be patient and let it do its thing.
See if you connect after that. If not, let me know and I will walk you through the next steps.
Regards,
KYTechnology