if your operating system is windows xp then you can click this link and follow the steps. but back first all your files.
if your are using windows vista or windows 7
1.Place the Windows Vista installation DVD in to your DVD drive, then reboot your system to allow the DVD to launch. At your first prompt, press any key to continue the process. Click Next and then click "Install Now" when prompted.
2.You will now be at the "Get important updates for installation" page. It is highly recommended (if you have an Internet connection at this point) to go ahead and install any available updates to ensure a successful installation. Once you've received the updates, click Next.
3.You will now be asked for your product key information. Your product key is located on your DVD case. Insert your 25 digit product key then click Next.
4.Now, you should be at the License Agreement screen. Feel free to read through the whole thing but it is going to take you quite awhile. You must "Accept" the licensing agreement to continue. Click Next once you're comfortable with the licensing agreement.
5.This next screen contains the main installation options. Select "Custom Install" (this is the correct option for a clean installation). Click Next.
6.Setup will now ask where you would like to install Windows Vista. You will see the available partitions on your system. You will need to select the "boot" partition (usually C:). If your boot partition has a previous version of Windows installed on it, you will want to delete this partition and the create a new boot partition. Create any additional partitions as desired, just be sure that each partition you create is formatted. Once you're done, click Next.
7.From here, the prompts may vary depending on your particular system. Just follow the on-screen prompts to install Vista to your systems configuration.
8.Once Windows Vista installs the necessary files to run, it will restart twice. It is important that you leave the installation disk in the DVD drive until the Windows Vista is completely installed. After the first restart, you will be asked to insert any Username and Password that you would like to use and a Name for your PC. Additionally, you will be asked for the following information:
Time and Date settings
Current Location (home or office)
After all of your information is successfully received, Vista will boot a second time. After it boots successfully, you can safely remove the Windows Vista installation DVD.
if you have the CDs for the drivers that you need install for the components of your system like the software for your wireless card, audio video and chipset, dont forget to install the also.
Congratulations! its done
i hope this helps
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