Are you able to post some debug logs from your client:
How To: Enable debug level logs for Symantec Encryption Desktop (formerly PGP Desktop) for Windows 2000 and XP
http://www.symantec.com/docs/TECH149847
If the issue is not with your local firewall and you have been able to contact before with the server can you try to ping and telnet to your server.
telnet IP_addres 9000
What are you getting please
I would also re-enroll the client:
HOW TO: Re-enroll PGP Desktop for Windows Clients
http://www.symantec.com/docs/HOWTO42029