When using Symantec Encryption Desktop (previously PGP Desktop) in a unmanaged environment and desire to use just one key to encrypt email to different email addresses, external users may request to use just one key for encryption.

The solution is to edit the policy so that Symantec Encryption Desktop only encrypts to a list of keys rather than try to find the specific key for the email address. Use the following steps to edit the messaging policy:

1. Open Symantec Encryption Desktop and click the PGP Messaging Control box.
2. Click Edit Policies next to Security Policies.
3. Select New Policy and type a name for the policy in the Description field.
4. Configure the conditions for the policy to encrypt to the domain and not to a specific key.  For example, set the policy like this: If any Recipient Domain is example.com.
5. Configure the conditions for the policy by selecting Encrypt to and a list of keys... from the drop down lists. 
6. Click Edit List and drag the desired keys to the Recipients list for which you want to encrypt the email and click on OK.
7. Click OK. The new policy is now displayed in the Security Policies list.

Now every email that is sent to example.com will be encrypted to the list of keys that was specified in the policy rule.