yes you can do it many time but one thing is important in that is you should have always your activation key of Windows which is most important thing in this.
The Refresh and Reset Utilities are accessible from General window in
Windows 8 PC Settings. To quickly open PC Settings, bring up charms
bar using Windows + C hotkey combination, click
Settings.
Now click on PC Setting.
When you click Get Started under Reset PC, it will show the
changes which will be made during the process. Insert Windows 8
installation disk, and then click Next followed by Refresh to reboot
the system.
For disk with multiple partitions, it asks you to choose entire hard
disk to perform the cleanup operation or only the disk where Windows 8
is installed. Just select the required option to move to next step.
Now, specify the type of cleanup operation – Thoroughly or Quickly.
The Thorough disk cleanup operation removes all the files from
selected disk(s), deletes all the installed applications, and makes
data irrecoverable, whereas the quick cleanup option simply deletes
your files and installed applications.
Now it will reboot your system and start
resetting Windows to default settings, The time it takes depends upon
the number of changes made to your system and total size of your data.
Once system reboots, it starts preparing your system for complete PC
reset. At the bottom, you will see Resetting your PC progress.
After the Resetting your PC process finishes, it will reboot your
system to update Windows 8 registry settings, find attached devices,
and then make identified devices ready for Windows 8.
Once the process is finished, you will be asked to enter the Product
key. Enter the license key and click Next. If you want to enter the
license key later, click Skip.
Now, accept License terms and click Accept to proceed further. It will
now start loading Windows 8, and you will see Personalization window.
Follow the on-screen instructions, enter details where required, and
let Windows 8 prepare a fresh desktop for you.
Will it save the product key? Or do I need to activate my PC again after resetting my PC? – NewUser – 2012-12-16T05:44:03.150
@DibyaRanjan No need product key will be saved – HackToHell – 2012-12-16T10:04:45.893
Do you know if it's possible to purchase multiple licenses from the same machine (I want to get a license key for my Dad but can't run the install from his machine)? – Neil Barnwell – 2013-01-22T10:00:19.407
@NeilBarnwell yes, you can. Buying retail version of Windows 8 allows you to install it to any pc. – HackToHell – 2013-01-22T11:59:47.917