To ensure the Manager Server is functioning properly, make sure the following ports are allowed from your internet provider or in software like RTP MIDI:
TCP ports from 2020 to 2052 should be open and unused.
UDP port 5008 should also be open and unused.
Multicast should be allowed.
There are other software like Firewall and some Anti-Virus software that may block the connection of the server, detecting its internal traffic between the device and the control panel.
If you have any anti-virus or anti-malware software, please uninstall it , reboot your system and check again if the manager server starts. You can also reload it in Antelope Launcher >System, under Manager Server.
If the Manager Server is not running, you can check if your provider is blocking some of those ports by switching the computer network to a mobile hotspot.