TrueCrypt is one of the best open source encryption solutions around. Here's how to use it.
TrueCrypt seems non-intuitive at first. Instead of directly encrypting drives and files, it makes you create pre-set containers first. And only other TrueCrypt users are able to open the containers.
Once you get that, TrueCrypt is powerful and easy to use on several OS platforms.
First, gather all of the data you want encrypt into one folder. It is helpful to do this early in the process. That way, you'll know what size to make the TrueCrypt container.
Go to the TrueCrypt website and download the version of TrueCrypt that's right for your OS.
Now navigate to the TrueCrypt Setup folder. Double-click TrueCrypt to launch it.
Complete the installation process with the default settings. For most users, those settings are fine.
After, if TrueCrypt doesn't open automatically, just launch it off the programs list. In Windows, do this by clicking on the Start menu. Into the search box, type: truecrypt
Now you need to create an empty TrueCrypt container that will hold the data you want encrypted. First, determine how large the container needs to be. If you already combined the data you want encrypted into a single folder, just right-click on the folder containing your data. Navigate to the General tab. There the folder size will display – I highlighted it in blue below.
Note: this number represents only the data currently in the folder. In order to plan for future additions, consider making the container two to three times larger than the folder's size. So, for the 69.1 MB folder above, a 210MB container would be ideal, allowing for extra space for future additions. Remember the size of the container you choose for later use.
To create a container, in TrueCrypt click Create Volume.
Choose Create an encrypted file container and click Next.
Click Select file. Choose where you would like to save the container and what you want to call it. Here, I labeled the container Financial Container and put it on the E drive. After you choose a location and name for the container, click Next.
Select an algorithm for the encryption. I recommend the defaults. They're excellent. Click Next.
Now choose the size of your container by entering numbers into the text box and selecting the units of storage. For this example I chose 210MB. That's because the file containing the data to be encrypted is around 70MB, leaving me 140MB of space for future additions. Make your selections and click Next.
Choose a strong password. No matter how strong the encryption is, if the password is weak, then the data will be vulnerable. Click Next.
Warning: BYTE at this writing knows of no workaround to let you recover this password or recover your data if the password is lost. The purpose of TrueCrypt is to make data irretrievable sans password. This is serious. Keep the password in a safe place and make multiple copies if you ever want to see this data again!