Windows will only format a drive as exfat if windows recognizes it as a removable drive.

Currently, you cant boot to an exfat formatted drive.

If windows recognizes your drive as removable, you should have a exfat format option like the picture shown.

Once youve formatted your drive, well need to create a Truecrypt container to keep our encrypted files.

At this point youll want to create an encrypted container and format it either NTFS or FAT.

Then:

Once youve created your container, mount it as a drive with Truecrypt.

We can, however, format the volume from the command line.

Using the following command:

format

/FS:exfat /Q

Format is a pretty basic command.

Replace

with the drive you want to format.

Truecrypt Volume in Windows 7 and OS X with large file support| Rowan Watson via Wayback Machine