Why is the availability of the service over UDP lost?

Question

Computer networks

Hello! Straight to the point: there is a service that runs on UDP port 475 (Hasp Loader). It spins on the same TCP port, but 1C does not know how to check client licenses using this protocol (at least officially, therefore we do not take this possibility into account). So, it works (Windows Server 2019), and then disappears from the list of open ports, although the service itself continues to work (remains on TCP 475) and, accordingly, the source of licenses for 1C clients disappears. On other systems (2008 R2, 2012 R2) similar services work without problems. I think one of the reasons for the failure to work over UDP can be broken packets (as an option, it receives too many of them and refuses to work further), so the question is: where to dig? Where can I put / uncheck some kind of checkbox: in the properties of the network adapter, somewhere in the system settings, or somewhere else?

PS Prior to this, this key worked properly on 7-ke. And before that, it refused to work on the 2003 server, and in the latter case, it completely crashed (disappeared from the list of running services), and not only the availability via UDP disappeared.

Answer 1

Maybe off topic. But I would disable ipv6 first

Answer 2

It spins on the same TCP port, but 1C does not know how to check client licenses using this protocol (at least officially

nethasp.ini
[NH_COMMON]
NH_TCPIP = Enabled
Useful article on keys: www.gilev.ru/nolic