What are the versions of your agent? I've seen installations with different versions of agents and servers work well, because the protocol is backwards compatible.
Also, the question you marked above has a suggestion for getting more details - does that help?
Finally, my guess is that maybe you have a firewall issue that is (likely) blocking port 7800 bidirectionally between your machines.
The software download is typically available to your company via ShareFile, and account access is given to one or more members when you're set up with the software. Your internal EC point of contact should have that information.