Thank you very much for your participation. Now everything has become clearer and I do not see an error in the behavior of the program. I think the question can be closed.
The only thing I'm wondering is why the Windows UPnP mapper implementation was rejected? -- You received this bug notification because you are a member of Dcplusplus-team, which is subscribed to DC++. https://bugs.launchpad.net/bugs/1993817 Title: Unable to create port mappings in DC++ with MiniUPnP mapper while other apps using MiniUPnP succeed Status in DC++: Confirmed Bug description: Tested DC++ up to version 0.880. Windows 10 x64. System Log: [17:35] Port mapping: Failed to initialize the MiniUPnP interface [17:35] Port mapping: Failed to map the Transfer port (54648 TCP) with the NAT-PMP interface [17:35] Port mapping: Failed to create port mappings I tried to select a specific network interface in the settings, disable all network interfaces except one. At the same time ApexDC++ and qBittorrent are successfully opened ports with UPnP. To manage notifications about this bug go to: https://bugs.launchpad.net/dcplusplus/+bug/1993817/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~linuxdcpp-team Post to : linuxdcpp-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~linuxdcpp-team More help : https://help.launchpad.net/ListHelp