Usually the m100 would register to a Gatekeeper and I am not to familiar if it can just dial an IP Address without being registered to such.
Another issue could be the PC's Firewall or a Firewall in your Network.
I would recommend your IT Team to run a wireshark trace to see if there is any outward communication from the Application to your Network.
The Ports that need to be opened on a Firewall have been discussed plenty of times and a forum search should highlight these for you.
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