Hard drive encryption is an integral step for anyone looking to secure their data. It is a process which will go a step beyond regular password security and will ensure that a hard drive remain secure only to the user. However, it is important to note that once a hard drive is encrypted, ITS can not remove the encryption so any files that cannot be accessed may remain that way until the user themselves can access them.
There are both paid and free software for OSX and WIndows, this guide will focus mainly on OSX 10.6 and above and Windows 7 and above.
Note: Drive encryption may require you to format your drive.
1. Apple OSX 10.8 Disk Encryption (free)
OSX 10.8 (Mountain Lion) provides an easy and very simple way for users to encrypt their external drives.
To encrypt a drive on OSX Mountain Lion, simply right click the drive, either in the finder window or on your desktop.
In versions 10.6 and 10.7 drive encryption should be accessible in the Disk Utility which can be found in your Applications/Utilities Folder. This drive encryption will ask you to erase your drive.
From here select the Encrypt option.
You will be presented with this window. Here, you can type the password you want to set for your drive and a hint that may help you remember it.
Remember: If you forget your password you will NOT be able to access your drive in any way.
Type in your password and hint and press Encrypt Disk
Note: If you run into this error, use this fix to correct it. This WILL erase your drive.
Open up the Disk Utility in your Applications/Utilities folder, select your drive and click on the partition tab
Click options to select "GUID Partition Table" and click apply.
When you press Encrypt Disk you will not see a progress bar or any sort of indication that the encryption process has begun. However, it is important that you DO NOT remove your drive until the process has finished. Depending on your drive, it may take a span of 3 minutes to 1 hour to encrypt the drive, the larger the drive the longer the wait. Be patient!
To check whether your drive has been encrypted or not, simply right click on the drive in your finder or your desktop and press Get Info.
You will see that under the drive description it now says Encrypted.
Now if you remove your drive and re-insert it, OSX will ask for a password.
To remove the encryption simply right click on the drive and select Decrypt.
2.Microsoft Windows BitLocker (free)
BitLocker is Windows' built in hard drive encryption software. It works on Windows Vista, 7, and 8. This guide will be using Windows 8 but the directions are mostly the same on all 3 operating systems.
Insert your drive, find it either in your sidebar in Windows Explorer, or in your Computer menu and right click it. From there, select Turn on BitLocker.
You will be greeted by the BitLocker screen.
You can now select options to encrypt your drive. We will be using password protection today.
Note: Your password MUST include an Uppercase letter, a Lowercase letter, and a number to be compatible.
Click next when you're ready to continue.
BitLocker also requires you to backup a recovery key which can be used to recover the data from your flash drive if it ever happens that you forget your password. You must perform this step in order to continue.
These two options allow you to either format the drive and encrypt it quickly, or perform a slower encryption which will attempt to retain any data contained in the drive.
You are given a small summary page before you are asked to continue, if any of these options are not to your liking simply press Cancel and start the process again.
The speed of the encryption depends on the size of the drive and which encryption option you chose. My 8GB drive took about 2 minutes to encrypt.
Now if you remove and insert the hard drive you will be asked to enter a password, or you can enter a recovery key and have Windows automatically unlock the drive every time you insert it into the PC.
When you unlock the drive, it should look like this in your Computer.
To remove the encryption simply right click on the unlocked drive and select Manage BitLocker from where you have several options, one of which is Remove password from this drive.
3.Alternative Encrypting Applications.
If the default operating system encryption methods don't work for you or you want something a little more secure or efficient, there are a few other third-party applications out there for your convenience. Some recommendations include:
GNU Privacy Guard (WIndows, OSX, Linux) - Free
TrueCrypt (Windows, OSX, Linux) - Free
7-Zip (Windows) - Free
AxCrypt (Windows) - Free