The Problem:

I switched on my PC after a normal shutdown only to see I had no internet connection. I called my ISP and they told me that my "Ethernet card" had gone out and that their modem was okay. I went out and buy a new PCI Gigabit adapter from TRENDnet and plugged it into my motherboard and updated the drivers on PC. I tried connecting again with resetting the modem and still no connection. I keep getting the error of "Unidentified Network" and PC keeps trying to "Identify" it.
As I have spoken with Comcast and even had a Tech person come out to my house to look at my setup? He tells me after replacing my modem and ethernet cable that my connection is well and after connecting his laptop to my modem he receives a good IP address and can surf the net. When connecting the modem back to PC and resetting it, I check my IP address and keep getting an address of 169.254.xx.x with a Subnet mask of 255.255.0.0 and no gateway listed. Both network adapters "are working properly". Sometimes I will get a 192.168.xx.x IP address when I first restart PC but it only stays for a matter of seconds before dropping back into the 169.254.xx.x.

My Computer:

I built my PC about 5-6 years ago and about 1 year ago replaced the Motherboard with a MSI brand motherboard for my AMD Quad Core Phenom processor. I have 2.0 GB of RAM. I am running a registered BETA version of Windows 7.

Solutions I have Tried:

• Power cycling/resetting the modem and even swapping Ethernet cables.
• I tested in Services menu to ensure my DHCP settings were enabled.
• I installed a new PCI Gigabit network adapter and updated the drivers from CD-ROM given. Uninstalled these later, then reinstalled.
• I scanned PC for Malware using Spyware Doctor.
• I stopped any Windows Firewalls and Spyware Doctor.
• I try "ipconfig /release" and "ipconfig /renew" in the command prompt. The renew command always times out and the release command usually gives me an error message.
• I reset winsock catalog using "netsh winsock reset" in command prompt.
• I reset TCP/IP settings with "netsh int ip reset" in command prompt.
• I pinged my local host (127.0.0.1) with a 100% working response of 0ms.
• Tested to ensure TCP/IP settings are trying to get an IP automatically.