Sql-server – “Connection failed” error when trying to telnet into SQL Server

I have an SQL Server running on a computer, and I'm trying to access it from another computer in the same local network (potentially VPN, since it's located in a datacenter). The point is that I can't even telnet to the port in which SQL Server is listening. And yes, SQL Server is working, since I can telnet to it from my workstation. I think it's something in the host, since there's no hop between the two computers, but I don't know how to troubleshoot this.
Basically I get a connection failed, when I try to telnet. What can cause such problem, since apparently there's no firewall and the server is accepting connections from other computers?

Thanks in advance