The DLP agent works as designed.
DLP agent identifies the TrueCrypt container (Virtual Drive) as Removable Storage. Basically this is expected behavior, the Truecrypt Virtual Drive is essentially a file which can be disconnected and move elsewhere such as USB, hence the reason why file based virtual drives are always treated as removable media.
The TrueCrypt application can mount the encrypted volume in different ways:
http://www.truecrypt.org/docs/favorites#Y604
We have the enhancement request (PM-2076) to add the following funcionality into the DLP agent:
- If the user will mount the TrueCrypt encrypted volume as Removable Medium, the DLP agent will identify the VHD as Removable Storage.
- If the user will mount the TrueCrypt encrypted volume as Fixed Drive, the DLP agent will identify the VHD as Fixed Drive.