Securely Wiping your PC

Blank Laptop

Secure Data Protection & Device Sanitization Procedure

(Preparing Windows PCs & Laptops for Resale, Donation, or Recycling) Back to Top

1. Purpose

This procedure ensures all personal and business data is safely backed up, verified, and secured before wiping a Windows PC or laptop. It guarantees that users don’t lose critical files, and that devices leave your custody with no residual personal information.

2. Pre-Wipe Preparation

2.1 Inventory & Planning

  • Record device serial number, model, and assigned user.
  • Identify data classification: personal, business, or sensitive/confidential.
  • Confirm outcome: Resale (with OS), Donation/Recycle (blank drive), or Secure Destruction.

2.2 Backup of Data

Step 1 – Triage Files

  • Essentials financial records, photos, work projects, legal documents.
  • Nice-to-have old downloads, non-essential media.
  • Discard junk files, installers, temporary data.

Step 2 – Choose Backup Method

  • Scenario A – Fast Internet / Cloud Available
    • Use OneDrive, Google Drive, Dropbox, or Azure.
    • Enable selective sync to avoid wasting bandwidth.
    • Verify by downloading a test file from the cloud on a second device.
  • Scenario B – Large Volumes / Limited Internet
    • Use external HDD/SSD/USB drives.
    • Run integrity check before use: chkdsk X: /f (Replace X: with the drive letter).
    • If unfixable errors appear replace media.
    • After copying mount on another PC, open random files, confirm folder sizes.
  • Scenario C – Low Connectivity Regions (e.g., rural Africa, Asia, South America)
    • Prioritize critical data only.
    • Compress archives (.zip or .7z) to save space.
    • Use multiple smaller USB drives if large capacity media is unavailable.
    • Make two physical copies (one personal, one stored with a trusted contact).
  • Scenario D – Very Large Specialist Data (media archives, research datasets)
    • Use NAS or multiple external drives.
    • For enterprise: ship drives to secure storage/data centers if internet is inadequate.

Step 3 – Verify Backup

  1. Compare folder sizes with originals.
  2. Open random samples (documents, spreadsheets, PDFs, images, videos).
  3. Confirm external drive remounts without errors.
  4. If migrating verify data and logins on the new device before wiping the old one.

Golden Rule: No wipe begins until backups have passed integrity check (chkdsk) and data verification.

3. Browser & Application Cleanup

3.1 Browsers

For each browser (Chrome, Edge, Firefox, Opera, Brave, etc.):

  • Turn off Sync.
  • Clear browsing history, cookies, cache, autofill, saved passwords.
  • Remove all extensions.
  • Sign out of all accounts.

3.2 Applications & Accounts

  • Sign out/deauthorize from:
    • Microsoft Account / Office 365 / OneDrive.
    • Dropbox, Google Drive, iCloud.
    • Adobe Creative Cloud, iTunes.
    • Steam, Epic, other gaming platforms.
  • Disable Find My Device.
  • Export license keys if required.

4. Secure Wipe Process

4.1 Standard Resale (Windows left intact)

  1. Settings Update & Security Recovery.
  2. Select Reset this PC.
  3. Choose Remove everything.
  4. Enable Clean the drive.
  5. Confirm Windows reinstalls and boots to Setup screen.

4.2 Full Wipe (Donation or Recycle, No OS)

  1. Boot DBAN USB or vendor secure erase tool.
  2. Run at least a 3-pass wipe for HDDs.
  3. For SSDs use Windows Clean the drive or manufacturer’s secure erase.
  4. Confirm drive shows as unallocated in Windows installer.

4.3 Highly Sensitive / Compliance Cases

  • Mandatory drive destruction shredding, degaussing, or certified physical destruction.

5. Post-Wipe Verification

  • Boot device:
    • Resale Windows Setup screen visible.
    • Recycle Drive unallocated.
  • Confirm no personal accounts remain.
  • Check BIOS/UEFI for residual owner info clear if needed.
  • Physically clean device (screen, keyboard, casing).
  • Package with charger/accessories.
  • Label: “Wiped & Verified – Ready for Reuse/Recycle”.

6. Staff Checklist (Summary)

☐ Record device details & intended outcome
☐ Triage files (essential/nice-to-have/discard)
☐ Select backup method (cloud/local/multiple drives)
☐ Run chkdsk on external media before backup
☐ Backup complete and verified on second device
☐ If migrating → test logins & files on new device
☐ Browser sync off, history/passwords cleared, extensions removed
☐ All cloud & software accounts signed out/deauthorized
☐ Perform appropriate secure wipe (Resale / Recycle / Destroy)
☐ Confirm successful wipe & boot state
☐ Device cleaned, accessories included, labeled

7. Best Practice Notes

  • Backups are worthless unless verified. Always check.
  • For SSDs, a single “Clean data” overwrite is enough; HDDs require multi-pass.
  • Always train staff: “No erase until backup verified and checked.”
  • For sensitive industries (finance, legal, healthcare) treat media as confidential until proof of destruction.

This is now a complete end-to-end standard:

  • Protects against accidental data loss.
  • Works in both high-bandwidth (London, NY) and low-bandwidth (Zambia, rural India) contexts.
  • Includes both human-facing steps (browser/account logout) and technical safeguards (chkdsk, wipe verification).

Apple machines have their own quirks: iCloud, Apple ID, iMessage/FaceTime, FileVault encryption, Safari keychain, and firmware locks. If those aren’t dealt with properly, the buyer may be unable to use the device – or worse, your data may still be recoverable.

Secure OSX Data Protection & Apple Mac Sanitization Procedure

(Preparing Apple Mac Computers for Resale, Donation, or Recycling) Back to Top

1. Purpose

This procedure ensures all user data is backed up, verified, and securely erased from Apple Macs before they leave custody. It prevents data loss and ensures devices are free of iCloud/Apple ID locks and ready for reuse.

2. Pre-Wipe Preparation

2.1 Inventory & Planning

  • Record Mac serial number (Apple Menu About This Mac).
  • Note assigned user and intended outcome: Resale, Donation/Recycle, or Secure Destruction.

2.2 Backup of Data

Step 1 – Triage Files

  • Essentials documents, photos, music, work projects.
  • Nice-to-have downloads, large movies, app caches.
  • Discard junk files, temporary data.

Step 2 – Choose Backup Method

  • Scenario A – Fast Internet / Cloud Available
    • Use iCloud Drive or third-party cloud (Google Drive, Dropbox, OneDrive).
    • Verify by downloading test files to another Mac/iPad.
  • Scenario B – Large Data / Limited Internet
    • Use Time Machine to an external HDD/SSD.
    • Or manually copy key folders (Documents, Desktop, Pictures, Music, Movies).
    • Run a disk check before use:
      • Open Disk Utility select external drive First Aid.
      • Ensure the drive passes without errors.
  • Scenario C – Poor Connectivity Regions
    • Prioritize only critical files.
    • Compress into .zip or .dmg bundles.
    • Store across multiple USB drives if large capacity disks unavailable.
    • Make at least two copies (personal + trusted backup).
  • Scenario D – Very Large Specialist Data
    • Use external RAID/NAS or ship drives to secure storage facility.

Step 3 – Verify Backup

  1. Mount backup drive on a different Mac confirm files open.
  2. Compare folder sizes with originals.
  3. Test iCloud restore/download on another device if cloud backup used.
  4. If migrating confirm accounts and files work properly on new Mac.

Golden Rule: No wipe begins until external drive passes First Aid, and backups are verified.

3. Account & Application Cleanup

3.1 Apple Services

  • Sign out of iCloud System Settings Apple ID Sign Out.
  • Ensure Find My Mac is disabled (removes Activation Lock).
  • Sign out of iTunes / Music, App Store, iMessage, FaceTime.
  • Turn off Keychain sync (saves passwords).

3.2 Applications

  • Deauthorize iTunes/Music: Menu Account Authorizations Deauthorize This Computer.
  • Sign out of Adobe Creative Cloud, Microsoft Office 365, Dropbox, Google Drive, etc.
  • Export software license keys if needed.

4. Secure Wipe Process

4.1 Standard Resale (macOS left intact)

  1. Restart Mac, hold Command + R to enter Recovery Mode.
  2. From Utilities open Disk Utility.
  3. Select startup disk click Erase.
    • For SSDs APFS, Secure erase not needed (data blocks are re-encrypted).
    • For HDDs choose Security Options 3-pass erase.
  4. After erase, choose Reinstall macOS.
  5. Let it boot to the Setup Assistant (ready for new user).

4.2 Full Wipe (No OS, for Recycle/Donation)

  1. Boot to Recovery (Cmd+R).
  2. Erase all partitions.
  3. Do not reinstall macOS. Leave drive blank.

4.3 Highly Sensitive Data / Compliance Cases

  • Remove drive and physically destroy (shred, crush, or degauss).
  • Macs with soldered SSDs require complete device destruction.

5. Post-Wipe Verification

  • Boot device:
    • Resale should show macOS Setup Assistant.
    • Recycle should show “No OS found.”
  • Confirm no Apple ID lock remains (test by booting Setup – it should NOT ask for Apple ID of old user).
  • Check BIOS/EFI (if corporate) for residual info and reset if required.
  • Physically clean Mac (keyboard, screen, casing).
  • Package with charger and accessories.
  • Label: “Wiped & Verified – Ready for Reuse/Recycle.”

6. Staff Checklist (Summary)

☐ Record serial number & outcome
☐ Backup chosen (iCloud / Time Machine / External drive)
☐ Run Disk Utility First Aid on external backup media
☐ Backup completed & verified on another device
☐ If migrating → confirm data and logins on new device
☐ Sign out of iCloud, iTunes, iMessage, FaceTime
☐ Disable Find My Mac (remove Activation Lock)
☐ Deauthorize apps (Adobe, Office, etc.)
☐ Wipe drive via Recovery Mode → Disk Utility → Erase
☐ (Optional) Reinstall macOS for resale
☐ Verify boot state (Setup screen or empty)
☐ Physically clean and package device

7. Best Practice Notes

  • Macs with FileVault enabled wiping disk is secure (encryption keys destroyed during erase).
  • Always disable Find My Mac – otherwise the buyer will be stuck with Activation Lock.
  • Run Disk Utility First Aid on backup drives before trusting them.
  • SSDs don’t need multi-pass wipes (data is encrypted and instantly inaccessible after erase).
  • Train staff: no erase until backup verified and iCloud fully signed out.

Linux isn’t just for sysadmins anymore; plenty of everyday users, students, and even small businesses run Ubuntu, Mint, Pop!_OS, Fedora, etc. They deserve the same data protection and sanitization rigor as Windows and macOS users.

The main Linux differences:

  • Lots of distros, but the core backup/erase steps are similar.
  • Common personal risks: browser logins, SSH keys, saved Wi-Fi creds, cloud syncs (Nextcloud, Dropbox, Google Drive integration).
  • Wiping is easier: shred, wipe, dd, or distro installers can nuke partitions.
  • Encryption (LUKS) is often enabled – wiping the header is enough to render data unrecoverable.

Here’s a Linux sanitization procedure in the same style:

Secure Data Protection & Device Sanitization Procedure

(Preparing Linux PCs & Laptops for Resale, Donation, or Recycling) Back to Top

1. Purpose

To securely back up, verify, and erase Linux systems before transfer. Ensures user data, SSH keys, and cloud syncs are removed, leaving a safe and usable (or blank) system.

2. Pre-Wipe Preparation

2.1 Inventory & Planning

  • Record hardware details (make, model, serial number).
  • Identify outcome: Resale (leave distro installed), Donation/Recycle (blank disk), or Destruction.

2.2 Backup of Data

Step 1 – Triage Files

  • Essentials /home/username/Documents, /Pictures, /Projects, config files (.ssh, .gnupg, .bashrc).
  • Nice-to-have downloads, package lists.
  • Discard cache, tmp files, large ISO images.

Step 2 – Choose Backup Method

  • Scenario A – Fast Internet
    • rsync to Nextcloud, Dropbox, Google Drive.
    • Test download of sample files on another machine.
  • Scenario B – Large Data / Limited Internet
    • Backup to external HDD/SSD via rsync or tar.
    • Run a filesystem check first: sudo fsck -f /dev/sdX (replace /dev/sdX with your external drive device).
    • If fsck shows errors that cannot be fixed replace the media.
  • Scenario C – Poor Connectivity Regions
    • Prioritize critical files only.
    • Compress into tarballs: tar -czvf backup.tar.gz /home/username/Documents
    • Store across multiple smaller USB drives if needed.
    • Make at least two copies.
  • Scenario D – Enterprise / Heavy Users
    • Use NAS or server rsync jobs.
    • Export package list for easy rebuild: dpkg --get-selections > pkglist.txt (Debian/Ubuntu-based systems)

Step 3 – Verify Backup

  1. Mount backup media on another Linux machine.
  2. Confirm file sizes match.
  3. Open random documents/photos/code files.
  4. If migrating confirm data accessible on new device before erasure.

Golden Rule: No wipe until backup passes fsck and sample verification.

3. Account & Application Cleanup

3.1 Local Accounts

  • Remove saved Wi-Fi connections: nmcli connection delete <SSID>
  • Clear browser logins (Firefox, Chrome, etc.).
  • Delete saved SSH keys from ~/.ssh/.
  • Delete GPG keys from ~/.gnupg/.

3.2 Cloud & Sync Accounts

  • Disconnect Nextcloud, Dropbox, Google Drive, Steam, Flatpak accounts, Snap logins.
  • Remove system keyring passwords: seahorse (for GNOME-based systems).

4. Secure Wipe Process

4.1 Standard Resale (OS intact, fresh install)

  1. Boot from USB installer of same distro.
  2. During install, select Erase disk and install.
  3. Choose to overwrite partitions (creates new FS).
  4. After install, boot to Setup screen (ready for next user).

4.2 Full Wipe (blank disk, donation/recycle)

Options:

  • Overwrite with dd sudo dd if=/dev/zero of=/dev/sdX bs=1M status=progress
  • Secure wipe tool (shred) sudo shred -v -n 3 -z /dev/sdX
  • For SSDs: use manufacturer’s secure erase command via hdparm: sudo hdparm --user-master u --security-erase-enhanced NULL /dev/sdX

4.3 Encrypted Systems (LUKS)

  • If using full-disk encryption:
    • Simply wiping the LUKS header makes data unrecoverable: sudo dd if=/dev/urandom of=/dev/sdX bs=1M count=10

4.4 Highly Sensitive Data

  • Remove drive and physically destroy.

5. Post-Wipe Verification

  • Boot machine:
    • Resale should launch fresh OS installer setup.
    • Recycle drive should be blank.
  • Confirm no personal data remains (lsblk should show new/empty partitions).
  • Physically clean machine.
  • Label: “Wiped & Verified – Ready for Reuse/Recycle.”

6. Staff Checklist (Summary)

☐ Record hardware details & intended outcome
☐ Triage files (essential/nice-to-have/discard)
☐ Select backup method (rsync/cloud/external)
☐ Run fsck on backup media
☐ Backup completed & verified on second device
☐ Remove browser data, SSH keys, Wi-Fi configs, GPG keys
☐ Disconnect cloud/sync accounts
☐ Perform secure wipe (installer erase, dd/shred, or manufacturer SSD wipe)
☐ Confirm wipe success (blank partitions or Setup screen)
☐ Physically clean & label device

7. Best Practice Notes

  • Always verify backups on another machine.
  • For SSDs, prefer manufacturer’s secure erase.
  • LUKS header wipe is instant & effective if encryption was enabled.
  • Train staff: “Never wipe until fsck is clean and backup verified.”