To begin the Windows 7 clean install process, you'll need to boot from the Windows 7 DVD.
Watch for a Press any key to boot from CD or DVD... message similar to the one shown in the screenshot above.
Press a key to force the computer to boot from the Windows 7 DVD. If you do not press a key, your PC will attempt to boot to the next device in the boot order, which is probably your hard drive. If this happens, chances are your current operating system will boot.
Note: If you existing Windows installation begins to boot or you see a "No Operating System Found" or "NTLDR is missing" error here instead of the screen above, the most probable reason is that your PC is not setup to boot to the CD/DVD drive first. To correct this problem, you'll need to change the boot order in BIOS to list the CD/DVD drive first.
Note: It's perfectly fine if, instead of the screen above, the Windows 7 setup process begins automatically (see the next step). If this happens, consider this step complete and move on.
You don't need to do anything at this point but wait for Windows 7 to finishing loading files in preparation for the setup process.
Note: No changes are being made to your computer at this time. Windows 7 is just temporarily "loading files" into memory for the setup process. You'll be removing everything on your computer as part of the Windows 7 clean install in a future step.
After the Windows 7 install files are loaded into memory, you'll see the Windows 7 splash screen, indicating that the set-up process is about to begin.
You don't need to do anything at this point.
Choose the Language to install, Time and currency format, and Keyboard or input method that you'd like to use in your new Windows 7 installation.
Click Next.
Click on the Install now button in the centre of the screen, under the Windows 7 logo.
This will officially begin the Windows 7 clean install process.
Note: Do not click the Repair your computer link at the bottom of the window even if you're completing this clean install of Windows 7 as part of some larger repair project for your computer.
The Repair your computer link is used to start a Windows 7 Startup Repair or perform another recovery or repair task from System Recovery Options.
Important: If you're performing a clean install of Windows 7 as a solution to a major problem but have not yet tried a Startup Repair, do that first. It could save you the trouble of completing this clean install process.
The Windows 7 setup process is now beginning.
No need to press any keys here.
The next screen that appears is a textbox containing the Windows 7 Software License.
Read through the agreement, check the I accept the license terms checkbox under the agreement text and then click Next to confirm that you agree with the terms.
Note: You should always read "small print" especially when it comes to operating systems and other software. Most programs, Windows 7 included, have legally binding limits on how many computers the application can be installed on, among other limitations.
Important: You are not breaking any laws or contracts by reinstalling Windows 7 via this clean install. As long as this particular copy of Windows 7 is only being operated on one computer, you're OK.
In the type of installation do you want? Window that appears next, you're offered the choice of Upgrade and Custom (advanced).
Click on the Custom (advanced) button.
Important: Even if you are upgrading from a previous operating system to Windows 7, I highly recommend that you do not follow the Upgrade installation. You'll get better performance with less chance of issues if you follow these clean install steps.
In this screen, you'll see each partition that Windows 7 recognizes.
The main difference in a Windows 7 clean install verses other kinds of Windows 7 installation methods is that a clean install involves the removal of all operating system related partitions.
Windows 7 setup considers partition management as an advanced task so you'll need to click the Drive options (advanced) link to make those options available.
In the next few steps you'll delete the partitions containing the operating system you're replacing with Windows 7, be it Windows Vista, Windows XP, a previous installation of Windows 7, etc.
Now that all available drive options are listed, you can delete any operating system related partitions from your existing hard drive(s).
Important: Before continuing, be aware that deleting a partition will permanently erase all data from that drive. By all data I mean the operating system installed, all programs, all data saved by those programs, all music, all video, all documents, etc. that might be on that particular drive.
Highlight the partition you want to delete and then click the Delete link.
Note: Your list of partitions may differ considerably from mine shown above. On my computer, I am performing a clean install of Windows 7 on a computer with a single 30GB hard drive that has previously had Windows 7 installed.
If you have multiple hard drives and/or multiple partitions on those drive(s), take great care in confirming that you're deleting the correct partition(s). Many people, for example, have second hard drives or partitions that act as backup drives. That's certainly not a drive you want to be deleting.
After deleting the partition, Windows 7 setup will prompt you to confirm the deletion.
The message says "The partition might contain recovery files, system files, or important software from your computer manufacturer. If you delete this partition, any data stored on it will be lost."
Click the OK button.
Important: As I spelled out in the last step, please be aware that all the data stored on that drive will be lost. If you have not backed up everything you want to keep, click Cancel, end the Windows 7 clean install process, restart your computer to boot back into whatever operating system you have installed, and backup everything you want to keep.
To be clear: This is the point of no return! There's no reason to be scared, I just want it to be very clear that you can't undo the deletion of the drive you selected after you click this OK button.
If there are any other partitions that need to be deleted, you can do so at this time.
For example, the Windows 7 installation I had on my PC previously created this special 100MB (very small) partition to store system data in. This is most definitely related to the operating system that I'm trying to completely remove from my computer so I'll delete this as well.
Highlight the partition and click the Delete link.
Note: As you can see, the partition we deleted in the last step is gone. It may appear like it's still there but if you look closely, you'll see that that same 29.9GB space is now described as Unallocated Space, not as a partition.
Just as in Step 12, Windows 7 setup will prompt you to confirm the deletion of this partition.
Click the OK button to confirm.
Important: Just as before, please be aware that all the data stored on this particular drive will be lost.
Installing windows 7 is not difficult at all if you follow the steps above