There are lots of encryption programs out there (there's even one built-in Windows Xp Professional) but a surprisingly easy and powerful free encryption software is Kruptos 2, developed by Steve Beckett.
Some of its main features:
- encrypts files/folders using 128-bit Blowfish algorithm
- obfuscates names of encrypted files, but leaves folder names unaltered
- integrates in the right-click menu (Windows Explorer)
- creates self-extracting encrypted files (having the .exe extension), that:
contain encrypted files and the software necessary to decompress the contents. Users can decompress the contents of a self-extracting file simply by running it like any other program.
- has a file shredder that uses dod standard (department of defense)
- it's free
You can download it here: Kruptos 2
Also, here's a quick tutorial on how encryption works with Kruptos 2:
- Select files/folders. The easier way it's to right click a folder (or file) in Windows Explorer, choose Kruptos 2 and after that Encrypt folder (file).
- Enter a password. Before the encryption starts, you have to choose a password for it. Also, you can enter a hint word, that later might remind you of the password you used, in case your memory is on a break. Note that once the password is set and the file encrypted, it's almost impossible to recover the file unless you know the password. So make sure you enter something you'll remember.
- Encrypt. Once the encryption is finished you'll receive a message about the status of the encryption (successful, failed). If you've encrypted a folder, you'll see that the name of the folder is the same but the name of the files are now completely changed and they show a "locked" icon.
- Decrypting the files. To decrypt, simply right click an encrypted file and select Decrypt. You will be prompted for the password and once that's entered and validated the files will be decrypted.
- File shredding. When you normally delete a file (using the simple Delete key), that file is not actually erased from your computer, and can be sometimes recovered. This is why, when you really want to delete a file you'd better use the File Shredding option. What this does, it's re-writing the file with a character, then the character's complement, and then a random character for a number of times specified by you (1-16). Given it's a method used by the Department of Defense, it's pretty sure that the file cannot be recovered.
That's it. Once you play a little more with Kruptos you'll see that's not difficult to use and it provides an additional security measure by encrypting sensitive data.