Protecting files from prying eyes

Some techniques for safeguarding your files.

When a file is encrypted and password protected nobody can read the file unless they know the password.

How to Password Protect and Encrypt files in Microsoft 365

For Word, Excel and Powerpoint – Microsoft 365 documents,

  • Click the File tab
  • Click Info
  • Click Protect Document (Word) or Protect Workbook (Excel) etc.
  • Click Encrypt with Password.

As with all password protected file mechanisms you will not be able to open or recover the files if you forget the password

How to Password Protect and Encrypt other files

AES Crypt is file encryption software available on several operating systems that uses the industry standard Advanced Encryption Standard (AES) to easily and securely encrypt files.

Using AES Crypt on Windows

To encrypt a file, right-click on the file you wish to encrypt, select the “AES Encrypt” option, and enter the required password. AES Crypt will create an encrypted file with the same name as the original file, but with an “.aes” extension.

e.g. IMG_4502.jpg will create a file IMG_4502.jpg.aes

When you encrypt a file with AES Crypt, it does not delete the original file. Generally, people encrypt files for the purpose of sending a file securely via e-mail or copying it to a portable storage device that is more susceptible to loss. As such, most people do not want to delete the original. However, you may certainly delete the original file: just do not forget the password.

It is impossible to recover the contents of an encrypted file if the password is lost.

To decrypt the file, right-click on the encrypted file, select the “AES Decrypt” option, and enter your password. This will create a copy of the original file

e.g. IMG_4502.jpg.aes will create a file IMG_4502.jpg

Details about using AES Crypt on other platforms is available at the website

and can be downloaded from

AES Crypt is free open source software.

How to Password Protect, Encrypt and compress files

7-zip and other file compression programs such as Winzip can be used to create encrypted files.

(7-Zip is the program I use on Windows Machines to create .zip files and is easy to install).

After installation, to create your compressed “zipped” file you right-click on a filename (or directory), select “Add to Archive” and choose your required options from a dialog:

Options are available to specify a password for the compressed file being created.

In order access the contents of the zip file you will need to enter the password used when the zip file was created.

Details about using 7-Zip is available at the website

7-Zip is free, open-source software. Most of the code is under the GNU LGPL license. Some parts of the code are under the BSD 3-clause License. Also there is unRAR license restrictions for some parts of the code.