How to encrypt a USB with files

[crescere]

I want to reliably encrypt a USB stick that already has files on it. From what I have seen programs have to create a container big enough to hold the files. So if my USB is almost full how do I do that?

 

[Troncoso]

You copy them onto a desktop, and then copy them back after installing your program.

 

[Agent Smith]

Use Truecrypt and create a container. Or I think you could encrypt the device. Although I haven't done that with a USB stick.

Read the whole manual! https://www.grc.com/misc/truecrypt/truecrypt.htm