It seems likely to me that there is some program or service running as part of the shipped bundle for those machines. This is assuming that these machines have generally working network connections.
Since your problem is network related, look for firewall software on those machines which is a different version (or differently configured) to your working machines.
Some firewalls block outbound connections from unauthorised programs. You may need to add your perl.exe to the list of programs permitted to do this.
