What is a simple, secure way to encrypt files in Windows?

Solution 1:

Although it might be a bit overkill, TrueCrypt allows you to encrypt files and folders and shows up as a removable device in My Computer. It is free and (in my opinion) user friendly.

Main Features:

• Creates a virtual encrypted disk within a file and mounts it as a real disk.

• Encrypts an entire partition or storage device such as USB flash drive or hard drive.

• Encrypts a partition or drive where Windows is installed (pre-boot authentication).

• Encryption is automatic, real-time (on-the-fly) and transparent.

• Parallelization and pipelining allow data to be read and written as fast as if the drive was not encrypted.

• Provides plausible deniability, in case an adversary forces you to reveal the password:

• Hidden volume (steganography) and hidden operating system.

• Encryption algorithms: AES-256, Serpent, and Twofish. Mode of operation: XTS.

Solution 2:

Check out AxCrypt. It's open source and made for encrypting individual files.

Solution 3:

There are two ways for this.

You can compress your file with some archiver like 7-Zip. They can encrypt the content. However, watch out because older versions of WinZIP for example doesn't use strong encryption. In contrast, 7-Zip uses strong AES encryption and can even encrypt file names.

Or you can use EFS. EFS works on NTFS. It doesn't ask you for a password because it uses your Windows credentials. It's important to know that this way you can't securely transfer your files. Your files are only encrypted on your HDD. If you use an USB flash drive or send a file in e-mail than it won't be encrypted.