I have my pc connected to my router by an ethernet cable. Recently when windows 7 has loaded the internet doesnt work and the only way to get it to work is to go into device manager and disable and enable the ethernet port.
Microsoft does have an official Windows 7 RC Support Forum located here http://tinyurl.com/9fhdl5 . It is supported by product specialists as well as engineers and support teams. You may want to check the threads available there for additional feedback and assistance.