John,
It seems like the update server is up, I just tried it and got no error. If you try it again, does it gives you that message?
If so, there may be some security settings, anti-virus/anti-spywares, network permissions, etc... that are preventing you from accessing the server. You may want to have your IT person double-check those settings.
In any cases, the updates can be downloaded from the web site. What version are you using? If it's 7.0.1, you have the latest version and do not need to upgrade(go to Help->About to find out what version you have). If not, you can go to our main web site, and go to Downloads->Software Upgrade->PlanetPress Suite.
Hope that helps.
Regards,
Rapha