Step 1. Open the “Start” menu
Click the Windows logo in the lower-left corner of the screen.
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Step 2. Open “Settings”
Click the gear icon in the lower-left corner of the “Start” window.
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Step 3. Click
"Updates & Security".
This circular arrow icon is on the “Settings” page.
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Step 4. Click Recovery
This tab is on the left side of the window.
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Step 5. Click Get started
It's at the top of the window, just below the "Reset this PC" heading. After that, a pop-up window will be displayed.
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Step 6. Click Remove everything
This option is in the pop-up window. Choose remove everything ” to ensure that no files, programs, or settings remain.
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Step 7. Click Just remove my files
This option is on the next page. With this option, Windows will remove any special programs, files, and settings, without removing the operating system itself.
If you want to do a more in-depth system reset, you can select the option “ Remove my files and clean my drive " Please note that this process can take several hours and you will need to reinstall Windows afterwards.
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Step 8. Click Reset
It's at the bottom of the window. After clicking Reset ”, the files will be deleted from the computer. Once the hard disk has been emptied, you will be taken to the initial setup screen where you can log into Windows as a new user.
Method 2 of 4: Clear Windows Computer
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Step 1. Make sure you have a blank DVD or USB drive
Before safely emptying your computer's hard disk, you will need to burn a program called "DBAN" to a blank DVD or copy it to a USB drive.
- You can verify that your computer's disc drive is suitable for burning CDs by looking for the "DVD" logo on or near the disc cross-section.
- If your disc drive can't burn DVDs, you can use an external disc drive (USB) that can burn DVDs.
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Step 2. Download the DBAN ISO file
Visit https://dban.org/ and click “ Download DBAN ” in the upper right corner of the window. After that, the DBAN disc image file (known as ISO format) will be downloaded to your computer.
You may need to confirm the download or specify a location to save the download before the file is downloaded, depending on your browser settings
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Step 3. Burn the DBAN file to DVD
Once DBAN has finished downloading, you can use the "This PC" program to burn the DBAN ISO file to a DVD.
- Make sure the DBAN DVD remains on your computer's disc drive after the burning process is complete.
- If you are using a USB drive, save the DBAN ISO file on the drive and make sure the drive remains attached to the computer.
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Step 4. Restart the computer
Open menu Start ”
click Power ”
and select Restart ” from the pop-up menu.
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Step 5. Access to BIOS settings
Immediately after clicking on the option “ Restart ”, press the computer BIOS button repeatedly. These keys are usually the Del key or one of the "F" keys (eg F2). However, you can find out which keys to press by checking the computer documentation/guidelines on the internet.
If you don't have time to access the BIOS, restart the computer and try entering BIOS setup again
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Step 6. Locate the "Boot Order" section
On most computers, use the arrow keys to select the "Advanced" or "Boot" tab.
Some BIOS models have a boot order option on the first page that appears
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Step 7. Select your computer's DVD drive
This option is labeled "CD Drive" or "Disk Drive" (or a similar label). Again, use the arrow keys to select the correct option.
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Step 8. Move the DVD drive to the top of the loading list
Once the " CD Drive " (or similar label) option is selected, press the + button until it is at the top of the loading list.
If that doesn't work, check the button legend on the right side (or bottom) of the screen to see which button to press to move the selected option
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Step 9. Save changes and exit BIOS
On most BIOS pages, you need to press a certain key. Check the button legend displayed on the screen to see which button to press.
On some computers, press another key again to confirm the change when prompted
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Step 10. Select the computer hard disk
After the DBAN interface is displayed, press the J or K key to move the selection up or down, then press the Space key once the computer hard disk is selected.
- Check the button legend at the bottom of the DBAN page to confirm which button needs to be used to toggle and select options.
- If you have multiple hard drives (or partitions) that you want to free up, don't forget to select them.
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Step 11. Empty the hard disk
Press the F10 key (or the key shown in the legend) to clear the disc. After that, the disc will be emptied immediately. This process can take (at least) a few hours so make sure your computer is connected to a stable power source.
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Step 12. Eject the DBAN DVD when prompted
After seeing the Blancco advert on the screen, you can take out the DBAN DVD. At this stage, the hard disk has been successfully emptied.
If you want to reinstall the operating system on your computer, you can replace the DBAN DVD with the desired operating system installation DVD and follow the steps shown on the screen. You may need to restart your computer to start installing the operating system
Method 3 of 4: Resetting Mac Computer
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Step 1. Open Apple menu
Click the Apple logo in the upper-left corner of the screen. After that, a drop-down menu will be displayed.
If your Mac uses a solid state drive type hard drive, resetting the computer is a much safer method for emptying the disk than the method followed when you use a regular hard disk (HDD)
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Step 2. Click Restart…
It's at the bottom of the drop-down menu.
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Step 3. Click Restart when prompted
Your Mac computer will restart immediately.
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Step 4. Enter recovery mode
When your Mac restarts, press and hold the Command key and the R key at the same time, then release when the " Utilities " window appears.
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Step 5. Select Disk Utility
This option is indicated by a gray hard disk icon with a stethoscope above it.
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Step 6. Click Continue
It's in the lower-right corner of the window.
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Step 7. Select the Mac hard drive
Click the option " HDD " or " SSD ” under the " Internal " heading that appears in the upper left corner of the window.
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Step 8. Click Erase
It's a tab at the top of the window. Once clicked, a pop-up window will be displayed.
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Step 9. Click the "Format" box
This box is on the right side of the page. A drop-down menu will appear after that.
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Step 10. Select Mac OS Extended
This option is in the drop-down menu.
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Step 11. Click Erase
It's in the lower-right corner of the window. Once clicked, the Mac computer's hard disk will immediately be emptied.
This process takes quite a long time. Therefore, refrain from doing a reset if you need to use the computer in the next few hours
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Step 12. Click Done when prompted
The computer's hard disk is now empty.
If you want to reinstall the operating system, close the Disk Utility window, click “ Reinstall macOS, and select " Continue " The computer must be connected to an internet source before macOS can be downloaded.
Method 4 of 4: Emptying Mac Computer
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Step 1. Open Apple menu
Click the Apple logo in the upper-left corner of the screen. After that, a drop-down menu will be displayed.
If your Mac uses an SSD, you can't free the disk. Instead, try to do a computer reset
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Step 2. Click Restart…
It's at the bottom of the drop-down menu.
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Step 3. Click Restart when prompted
Your Mac computer will restart immediately.
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Step 4. Enter recovery mode
When the computer restarts, press and hold the Command and R keys at the same time, then release them when the " Utilities " window appears.
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Step 5. Select Disk Utility
This option is indicated by a gray hard disk icon with a stethoscope on it.
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Step 6. Click Continue
It's in the lower-right corner of the window.
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Step 7. Select the Mac hard drive
Click the option " HDD ” under the " Internal " heading on the left side of the page.
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Step 8. Click Erase
It's a tab at the top of the window. Once clicked, a pop-up window will be displayed.
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Step 9. Click Security Options…
It's at the bottom of the window.
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Step 10. Select the “Most Secure” option
Click and drag the slider to the far right to select the "Most Secure" option. This option works to overwrite a Mac's hard disk with blank information seven times in a row.
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Step 11. Click OK
It's in the lower-right corner of the window.
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Step 12. Click Erase
It's in the lower-right corner of the window. After that, the hard disk will be emptied immediately.
The "Most Secure" option usually takes a few hours to complete. You may be able to start the process of clearing the computer before going to work or before going to bed
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Step 13. Click Done when prompted
The Mac's hard drive is now emptied. Data recovery may also be very difficult to do afterwards.