If your computer is becoming sluggish, a fresh start may be in order. Wiping and reinstalling your operating system on a regular basis can keep your computer running smoothly for much longer than you might expect. This will remove junk files and crust that are slowing down performance. If you back up your files on a regular basis, the entire process should only take an hour or so.
Method 1 Windows
1. Get or make a Windows installation disc or USB drive. Using a Windows installation disc or USB drive is the simplest way to wipe your computer and start over. This must be the same version of Windows as the one you currently have installed. For example, if you want to instal Windows 7, you’ll need a Windows 7 installation disc. You can either use the disc that came with your computer or make your own. A blank DVD or a USB drive with at least 4 GB of storage is required:
Windows 7 – Download the ISO file from Microsoft using your product key. Then, using the ISO file that you just downloaded, download the Windows DVD/USB Download Tool to create an installation DVD or USB drive.
Windows 8 users should go to the Microsoft Windows 8.1 download page and click the “Create media” button. Launch the tool and follow the on-screen instructions to download and create an installation DVD or USB drive.
Windows 10 – Navigate to the Windows 10 download page and select the “Download tool now” option. To download the Windows 10 files and create an installation DVD or USB drive, follow the prompts in the tool.
2. Make a backup of any files you want to keep. All of the files on the drive will be erased if you wipe your computer and reinstall Windows. Make a backup of any important files in a safe place, such as an external hard drive or a cloud storage service. After you’re finished, you’ll need to reinstall any programmes you have.
For information on backing up your important files, see How to Back Up Data.
3. Start the computer by booting from the installation disc or USB drive. After you’ve backed up everything important, you’re ready to begin the wipe and reinstall process. Instead of your hard drive, you’ll boot your computer from the installation disc or drive. You must configure your computer to boot from the installation disc or drive you just created. The procedure differs depending on whether your computer was pre-installed with Windows 7 or later, or with Windows 8 or later (BIOS vs. UEFI).
Windows 7 (or an earlier version) (BIOS) – After restarting your computer, press the BIOS, Setup, or Boot key. This key will be displayed on the screen before Windows loads while your computer is booting. F2, F10, F11, and Del are examples of common keys. Set your DVD or USB drive as the primary boot device in the BOOT menu.
Windows 8 (UEFI) or later – Right-click on the Power button in the Start menu. Shift-click “Restart” while holding down Shift. Select “Troubleshoot” from the resulting menu, followed by “Advanced options.” To access your UEFI menu, click the “UEFI Firmware Settings” button. This menu’s Boot section allows you to change the boot order so that your computer boots from the USB or DVD drive.
4. Begin the installation procedure. When prompted to launch the Windows Setup programme, press any key on your keyboard. It may take a few minutes to load all of the required files.
5. Choose your preferred language. You will be prompted to choose your language preferences before the installation begins. After making your selection, click “Install now” to begin the installation.
6. Please enter your product key. If you’re installing Windows 8 or later, you’ll be prompted for your Windows product key. After you finish installing Windows 7, you will be prompted for the product key. If you want to enter your product key later, you can skip this step.
7. Choose the “Custom” installation method. This will allow you to erase all of your computer’s data and start over.
8. Choose the drive where Windows is currently installed. It will be labelled with your Windows version and listed as a “Primary” drive.
9. Click the “Drive options” button, followed by “Delete.” This will delete the partition as well as all of the data on it. It will be renamed “Unallocated space.”
You can do the same thing for any other partitions you want to remove and merge into your main one. Any data on these partitions will also be erased. To combine a block of unallocated space into a single partition, click “Extend.”
If you want, you can divide your partition into multiple partitions. This could be helpful for file organisation. To create new partitions from unallocated space, select the unallocated space and click “New.” Simply ensure that the partition on which you intend to instal Windows is at least 20 GB in size.
10. Select the partition on which you want to instal Windows and press the “Next” button. This will start the Windows installation process. It will take about 20 minutes to copy and instal everything.
11. Create an account for yourself. After the files have been copied, you will be prompted to create a user account. This account will have administrative rights. You’ll also be asked to give the computer a name. This is the name by which your computer will be identified on the network.
12. Enter your product key here (Windows 7). When installing Windows 7, you will be prompted to enter your product key. If you plan to enter your key later, you can skip this step for now.
13. Select your Windows Update options. Most users should choose the “Recommended” options to keep everything up to date and secure.
14. Decide on a date and time. Your computer should choose the correct date and time for you, but you may need to make manual adjustments.
15. Determine the type of network to which you are connected. Select the network type that best fits your needs. This will have an impact on your network’s security and sharing settings.
16. Begin using Windows. You’ll be taken to the Windows desktop after selecting your network type. If you did not enter your product key previously, you will be prompted to do so now.
Method 2 Mac
1. Make a backup of any important files. All of your files will be deleted when you reinstall OS X. Make a backup of all important documents, photos, videos, and other files to a secure location, such as an external hard drive or a cloud storage service. For information on backing up your important files, see How to Back Up Data.
2. Reboot your computer and hold .⌘ Command+R after the startup sound. Release the keys once you see the Apple logo.
3. Choose the Wi-Fi network to which you want to connect. You may be asked to select the network to which you want to connect. If you don’t have Wi-Fi, you’ll need to use Ethernet to connect. To reinstall OS X, you’ll need an internet connection.
You can also select a network by clicking the Wi-Fi icon in the upper-right corner.
4. From the Recovery menu, select “Disk Utility.” This will open a new window displaying all of your computer’s installed drives.
5. Select your hard drive and press the “Erase” button. You can leave the default settings in place and rename the drive if you want. To confirm, click “Erase.” To return to the Recovery menu, close Disk Utility once the erasing process is complete.
6. Click “Continue” after selecting “Reinstall OS X.” This will launch the Mac OS X installer. You will be notified once your computer has been verified by Apple.
7. The licence agreement must be read and accepted. To proceed with the installation, you must confirm that you accept this.
8. Choose the drive where you want to instal OS X. In Disk Utility, select the drive that you just erased.
9. Fill in your Apple ID. You’ll be prompted to enter your Apple ID to confirm that you own the operating system licence.
10. Allow time for the files to download. The installer will begin downloading the files required for OS X installation. The time it takes will be determined by the speed of your internet connection.
11. Select your region and keyboard. These should be selected correctly by default.
12. Log in to your network. To connect to a wireless network, select it and enter its password. You will not be prompted to select a network if you are connected via Ethernet.
13. Select the option to transfer data. You can use Time Machine to restore a backup or transfer files from a Windows PC. If you select either of these options, follow the on-screen instructions to transfer the files. Select “Don’t transfer any information now” to set up as a new computer.
14. Log in using your Apple ID. This grants you access to the Mac Store as well as your iTunes purchases.
15. Make an account. OS X will use your Apple ID as your computer account by default. Instead, you can set up a local account.
16. Complete the setup procedure. Before you’re taken to your new desktop, you’ll go through a few more minor setup screens.
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