Follow below steps:

1. On your Old Machine, Install Mail Migration add-on for Internet Explorer
2. Sign in to the Mail account for which you want to move
3. Follow the on screen Instruction till done
4. Now, go to Windows 8 Machine & go to Mail/People App
5. Open Settings and click on Accounts
6. Click Add an account and select your account
7. Enter mail id & password for the Microsoft Account where your contacts & email were moved to.
8. Click Connect. Your account with your contacts/address book will be available in the Mail app.