In order to upgrade to Windows 7 on a computer running on Microsoft's Windows XP operating system, you do not have to uninstall XP first. Instead, you'll have to select the "Custom" option early on in the upgrading process. This "Custom" installation can take up to several hours to complete.
Preparing Your Computer
Before beginning the upgrade process, you'll want to back up all your files and programs on an external hard drive. This is because a custom installation does not preserve these items; for this reason, it is sometimes referred to as a "clean install." Connect your computer's hard drive to an external drive using a USB cable and move all the programs, files and settings you wish to save and transfer back to your computer after the upgrade is complete. If you don't have an external hard drive, you can also store the data on a CD, hard or floppy disc or a USB flash drive; keep in mind most of these options cannot store as much material as an external hard drive and may not be able to store all the information you wish to save.
Before starting the upgrade, you'll also want to make sure your computer is connected to the Internet. This way, the program can check for updates to Windows 7 during the upgrade process to make sure you get the most current version of the operating system.
Also, run your antivirus software before beginning the upgrade. After the software does a complete sweep of your computer to remove any problems, turn it off; keeping it on during the upgrade could slow down the process or even prevent some components of Windows 7 from installing properly.
32-bit vs. 64-bit
There are two different versions of Microsoft Windows 7: a 32-bit version and a 64-bit version. Installation discs for both versions are included with your Microsoft Windows 7 purchase. The difference between these two versions is the amount of memory each can handle. Windows 7's 64-bit version can handle up to 4 gigabytes (GB) of memory, called "RAM," significantly more than the 32-bit version. To see which version is compatible with your computer, click on the "My Computer" option inside your Start menu. Next, select "Properties." Look for "x64" -- if you see this property, you are currently running a 64-bit version of Windows XP and should upgrade to the 64-bit version of Windows 7; if "x64" is not listed, you're running the 32-bit version of XP and should upgrade to the same version of Windows 7.
You have two options when it comes to obtaining Windows 7. The first option is downloading the operating system; this is most commonly -- and legally -- done using Microsoft's website (see Resources). After purchasing the rights to the operating system, you can download it straight to your computer, where you can either opt to launch it right away or save it for future installation.
The second option is installing Windows 7 using a disc. This is how you'd install the operating system if you purchased it from a store. When you insert the disc into your computer's tower, the installation window should automatically display on your computer's screen.
Regardless of which option you choose, you'll be given a 25-character code. This product key will be emailed to you if you purchased a digital copy of the operating system online or should be on the packaging containing your Windows 7 discs. You'll be prompted to enter this product key before you'll be able to install the operating system.
Launching The Installation
After you select "Custom" from the first pop-up window, you'll be asked to specify which version of Microsoft Windows you're computer currently uses. Look for the section on the proceeding window called "XP." Clicking the "Next" button will produce another pop-up box called "Windows.old." Click "OK" on the button in this box to continue with the installation process using the installation wizard. After you go through all the steps and prompts using the installation wizard, you will have to restart your computer to complete the upgrade process. The last and final step is to reinstall the programs and files you saved to your external hard drive or other source.