If you initiate the Setup routine from within Windows XP or Windows Vista, the step-by-step procedure is as follows:
1. Insert the Windows 7 DVD into your computer's DVD-ROM drive. It should AutoPlay and present the Install Windows dialog box. If not, locate and double-click the setup.exe program in the Sources folder on the DVD.
2. To download, install, and use the Windows 7 Upgrade Advisor, click the Check Compatibility Online link. Otherwise, to begin the in-place upgrade to Windows 7, click the Install Now link.
3. In the Get Important Updates for Installation dialog box, you are asked whether you want to download updates to the Windows 7 install files. Typically, for computers that have an active Internet connection, you're better off getting the updates. Make your selection by clicking it.
4. In the Please Read the License Terms dialog box, ensure that you read and understand the End User Licensing Agreement (EULA). When you're ready, select the I Accept the License Terms option and click Next to continue.
5. In the Type Your Product Key for Activation dialog box, you are asked to enter your Windows 7 product key. Enter the key and ensure that the Automatically Activate Windows When I'm Online option is checked, to enable Windows Product Activation. After entering the product key, click Next to continue.
6. In the Which Type of Installation Do You Want? dialog box, shown previously in Figure 2.10, select Custom (Advanced) because you're performing a clean installation here on top of an existing Windows XP installation.
7. In the Where Do You Want to Install Windows? dialog box, shown in Figure 2.20, select the partition onto which you'll install Windows 7. When you're ready to proceed, click Next.
8. The Setup application warns you that the selected partition contains files from another Windows installation, as shown in Figure 2.21. After you read this information, click OK to continue.
9. The Installing Windows dialog box appears and updates the status for the upgrade process.
10. From here, the rest of the process is just like that for a clean installation (on a blank hard disk) above, starting with step 9. After some time, your computer restarts and the newly installed Windows 7 loads.