Not all files encrypted when copied to Endpoint Encryption USB stick

I am testing the latest trial version of Symantec Endpoint Encryption v.11 in the lab. That's what I have done so far:

- Created and installed the MSI packages on a PC for: Management Agent Client and Removable Media Encryption Client (with the setting to encrypt new files)

- Connected a newly formatted NTFS USB stick to the PC

- Copied a few DOC, EXE files to it from network drive

- Created a new TXT file on the USB stick

- Disconnected the USB stick from the PC and connected to another PC

I found that the EXE and TXT file were ncrypted however the DOC file wasn't encrypted for some reason.

Is there any way to enforce the policy so that ANYTHING that had been copied to the USB stick, need to be encrypted?