How to Set Up Backups for a Windows 7 Home Network
Click Save on a Network. Then, enter the network location manually in the format \\server\share. Under Network Credentials, enter a Username and Password that Windows Backup can use to access the network.
Server is the name of the computer that you will be saving your backups onto and share is the folder on that computer. You can also click Browse to navigate directly to the computer and folder. Keep in mind that the network location must be available at the time the backup is scheduled to run.