You have installed PGP 10.0.0 as unmanaged client and rebooted the server. During the enrollment process, when you are trying to activate your license, by entering the license key, you get an error that the destination host is unreachable. There are no firewall issues and none of the ports are blocked.
Your current license key is no longer valid or has expired for your older versions of PGP.
The license key is now linked to your new versions of PGP.
You need to install or upgrade to the newer versions of PGP to resolve this issue.
Install versions of PGP which are 10.2 and above and then you will not get any errors while activating you PGP license.
PGP 10.0.0 installed as unmanaged client.