There is no direct migration path from Symantec Encryption Desktop 10.x to Symantec Endpoint Encryption version 11.0.1. This is being addressed in the next Endpoint Encryption major release, 11.1.0.
Currently, you would need to decrypt the system, then you should be able to utilize the Symantec Endpoint Encryption v11.0.1. You don't need to uninstall the Symantec Encryption Desktop, but for SEE drive encryption to function, SED (PGP) drive encryption must be out of the picture. Also, you must have the Management Agent Client installed before you can install the Drive Encryption Client.
Landing page for SEE v11 is here for documentation:
https://support.symantec.com/en_US/endpoint-encryption.55414.html