Windows 7: Win 7 RTM No internet connection

I downloaded the RTM for Win 7 Pro x64, build 7600 from MS Software Assurance and installed it as an upgrade to Vista Pro. All seemed to go OK until I tried to connect to the internet. I can connect to the other computer on the network (wired through a Linksys WRT160NL router and also running Win 7) and transfer files between the systems. The other system connects fine to the internet. My main system does not, and has a red X in the Network and sharing center.

The system is ASUS P6T Deluxe motherboard, Core i7 processor, 6 GB RAM, Lan is Marvel Yukon 88E8056. Router is connected to a Linksys CM100 cable modem via ethernet cable.

I have restarted/rebooted everything, changed cables, checked the LAN driver (latest) with no success. I worked fine with Vista and if I restore the Vista C: image it all works again. Reinstalling Win 7 gives the same problem.

Any ideas?

Did you install photoshop or adobe creative suite? Or some other Adobe or Apple software?

Open a command window and type "ipconfig". If you see the address 0.0.0.0 as one fo the addresses for your "Gateway" for any of the listed adapters, you may have to disable "Bonjour", an apple IP PNP service that doesn't play well on a lot of Windows 7 installs.

I got this off the groups here, but cut and pasted for brevity:

a) Open a command window with admin privs. (Type "cmd" int he start->Search window, then right click the "cmd.exe" listed and "Run as Administrator")
b) cd \Program Files (x86)\Bonjour
c) mDNSResponder.exe -remove
d) regsvr32 -u mdnsNSP.dll
e) reboot