This is the software publisher’s description.

CryptoExpert Professional enables you to create encrypted virtual disks which are visible as your usual disks, within Windows Explorer, and are allocated drive letters (for example, G:, H:). It uses a 256 bit encryption key to protect the data stored within your encrypted drive.

All data stored on an encrypted CryptoExpert disk is stored in a container file. A container is a usual file, so if you are the password holder, it is possible to backup a container, move or copy it to other disk (CD-ROM or network, for instance) and continue to access your encrypted data using CryptoExpert. Any free drive letter available from your system may be used to mount and to open an encrypted file-container for access.

When you need to access your data on the virtual disk, you can read and write data as if it were a conventional removable disk. You can do anything with a CryptoExpert virtual drive that you can do with a normal hard drive.

Note that this is the Professional edition. There is also a free Lite edition.