I am having the EXACT problem as described in this post.
"How to update Realtec NIC drivers during a WHS Bare Metal Restore"
http://social.microsoft.com/Forums/en-US/whsfaq/thread/b14e3cf2-7b02-4569-8c26-c75b7a58d6e7
The symptoms are 100% accurate. Unfortunately the links to the Realtek NIC drivers are no longer working. I spent 4 hours scouring the net, and downloading various drivers, with absolutely no luck. I found ones from other websites that
said they were going to work but they did not. I should have realized that I can just buy a NIC at the store tomorrow and worry with it then. Does anyone have any other idea on where to find them? I think I shall email Realtek also.