Windows 7 Clients with Removable Media Encryption (RME) drives, do not show the lock icon when the file is encrypted on the RME.
Windows 7 only
Symantec Endpoint Encryption
Removable Media Encryption
Windows 7 registry Overlay Keys are limited to 15 entries, to be active in the system.
The Windows 7 Overlay key for Symantec, may be past the 15th Overlay key listed, thus making it inactive.
After backing up the registry, rename the Symantec Overlay Keys so they appear at the top of the Overlay list. They are sorted alphabetically. Once this is done, a reboot may be required for the lock icon to appear on the RME.