http://www.whshelp.com/articles/WHS%20b ... 0fails.htm
If there is a “zero” next to “Network devices”, or “Storage devices”, you must add the appropriate drivers. Because the backup is stored on the WHS server, you must have network connectivity.
Click “Show Details” to see what the Restore CD was able to find.
Click “Install Drivers”
Insert the USB (or floppy) drive that contains the drivers for your PC. If you don’t have these handy, follow article “How to restore PC drivers”.
If you have the correct drivers, then you will be notified. This is an important step that cannot be skipped.
Notice that the Restore Client has found and installed the network drivers for the AMD PCNet Adapter device. It is now safe to click “Continue”.