How to encrypt and protect files and email messages

The content we send by email or that we store on our devices or on a "cloud" server can be appealing to possible malicious actors. Data breaches are one of the most common consequences of cyber-attacks. Therefore, one of the ways to prevent the harmful effects caused by a cyber security incident is to encrypt this data or create folders with restricted access, adding a layer of protection on top of all the other precautions essential to cyber security.

Encryption consists in transforming a readable content into something unreadable, but that can be converted back into something readable by means of a key. It may not be necessary to apply this technique to all the content we save or share, but for some it may be worthwhile. For example, some files contain personal details such as bank accounts or medical check-ups. Others are private photographs or videos. These types of content can be especially protected in case our devices or our account on a cloud platform are compromised.

Also, some emails are more sensitive than others. Sometimes we share files with personal data or write messages with information that is critical from a personal or professional point of view. In these cases, it can be important to create that extra layer of security. Nothing is 100% protected, and this type of care can be circumvented by very sophisticated techniques, but the more difficult we make the access to our data and devices, the better. Therefore, we suggest a set of sources of the most used brands where you can find simple and short tutorials that help to encrypt and protect files and email messages according to the products in question.

1. Windows operating system is one of the most common. So check out these Microsoft pages where you can find simple tutorials on how to encrypt files in Windows: here and here. 
2. Apple brand computers, also very well known, use their own operating system, macOS, which also allows you to encrypt files, both on the computer and on removable devices. To do so, refer to these pages: here, here and here.
3. Google's widely used Android smartphone operating system provides a service called "secure folder", which protects the files you place inside by means of a 4-digit PIN. To find out how: here.
4. In the case of smartphones of the Apple brand, the iPhones, which use the iOS operating system, there is a service that allows you to protect your notes through a password, Face ID, or Touch ID. Follow the instructions: here.

Note: there are several applications on the market that allow you to perform operations that encrypt files. If you purchase one, choose those that are sold on recognised platforms, that meet your needs, and that have good reviews from users and experts. There are also open source programs that can be good options.

1. If you use Microsoft's Outlook service as your e-mail management platform, you can learn how to encrypt your emails: here.
2. If you use Google's Gmail email service, there is a tutorial available on this page: here.
3. For those who use the Exchange environment on Apple's iOS and want to encrypt an email, you can follow these steps: here. 

Note: in any of these cases that allow encrypting email messages, it is necessary that the application supports the S/MIME standard, which allows you to use a set of security specifics when sending emails. For more details, please check the following page (in English): here.  
Esta camada de proteção não substitui outras tecnologias essenciais para a segurança do email, como o protocolo TLS.
This protection layer does not replace other essential technologies for e-mail security, such as the TLS protocol. For further information on this subject and this type of features, we recommend reading about the PGP (Pretty Good Privacy).

Warning: All shared pages were last accessed on 3 May 2022. Possible outdating may result from innovations of the products concerned. The choices of these examples result from their popularity of use and not from cyber security-related criteria.