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UiL OTS Labs

How-tos

Encrypting files for storage or transportation

Last updated on 3 March 2016 by Jan de Mooij

If you have suggestions on how to improve this document, or find mistakes, please send them to labman.gw@nulluu.nl

If you work with sensitive of private information and you need to move your files from one location to another, you are obliged to do so in a safe manner.

Within the lab, we offer access to project folders to exchange data with people who have permission to see the data only. However, sometimes you will need to move data between different machines outside the lab, without access to internet, or to the project folders. In that case, you may use a USB flash drive.

If you use a USB drive, we advice to encrypt the data, so only you have access to it, even if you accidentally lose the flash drive that has all the data on it. This way, no one else can view the data.

This tutorial uses 7zip, a free compression tool, to encrypt the data. To encrypt the data, 7zip needs to be installed on the machine you want to encrypt the data on. To view or decrypt the data later, you need 7zip on the machine you are going to view the data on. You can download 7zip here. These instructions only work when 7zip is installed.

If you borrow a USB flash drive from the lab, these instructions will be attached to the USB drive.

  1. Open the file explorer
  2. Navigate to the file or folder you wish to encrypt
  3. Right click the file or folder you wish to encrypt
  4. Click 7zip –> Add to archive
    1. Archive format: 7z
    2. Compression: Store
    3. Enter password (twice) in the Encryption field
    4. Click Encrypt file names (otherwise, people without a password can still browse the file list)
  5. Do not forget the password you entered
  6. Click Ok

  1. Open the file browser
  2. Navigate to the file or folder you wish to encrypt
  3. Right click the file or folder you wish to encrypt
  4. Click Compress
  5. Select .7z as the extension (on the right of the file name)
  6. Select the save destination for your encrypted file as the location
  7. Open other options
  8. Enter a password
  9. Make sure Encrypt the file list too is selected
  10. Do not forget the password you entered
  11. Click Create

For opening: Double click the .7z file. 7zip now asks for a password. Enter the password to view the files.

For extracting / decrypting:

  1. Right click the encrypted file
  2. Click 7zip –> Extract files
  3. Enter password and select a location where to extract the files to

  1. Double click the file
  2. Enter your password
  3. Click Extract