PGP Encryption Desktop licensing

I am looking at the PGP desktop latest version.  I have installed the trial with the licensed features turned off - all we really need to do is decrypt incoming system generated email.  We won't use anything else except the email decryption feature.

I need to create a new key but having done this when I export the public key it says:

Version: Encryption Desktop 10.3.0 (Build 8741) - not licensed for commercial use: www.pgp.com

Do I need to buy licenses to use the software in this way - I am able to load the PGP viewer and this is the only feature I want our users to have.

How do I create a license key that is licensed for commercial use?

Thanks

James.