PGP Universal Server fails to send encrypted emails to external users because the external user's public key is not found.
The solution to this issue is to configure PGP Universal Server to search for public keys of external users on the PGP Key Server.
This can be achieved by following these steps:
Open the PGP Universal Server and click Mail and then Mail Policy.
Click on the effective outbound mail policy and click on the effective policy rule.
In the Key Search tab click on the plus sign for Search for Keys in Additional Locations.
In the drop down, select Add New Key Server and give the external users key server information in the popup window.
This will allow PGP Universal Server to search for keys with the email address in the external users key server. If the keys is found then it will send the email encrypted. PGP Universal Server can also search for keys in the PGP Global Directory. To do so, please follow the link below: