I'm still stuck on the same problem.
I already tried disabling UPnP and turning it on again.
Also my Firewall doesn't block zandronum connection.
I do not know if I am doing well the steps to follow. Because in reality I have already tried everything and nothing works so I went to the sacred community of knowing of zandronum.
This is what I get in the console:
IPFileParser::parseIPList: could not open adminlist.txt: No such file or directory
IPFileParser::parseIPList: could not open whitelist.txt: No such file or directory
IPFileParser::parseIPList: could not open banlist.txt: No such file or directory
S_Init: Setting up sound.
ST_Init: Init startup screen.
Checking cmd-line parameters...
S_InitData: Load sound definitions.
G_ParseMapInfo: Load map definitions.
Texman.Init: Init texture manager.
ParseTeamInfo: Load team definitions.
LoadActors: Load actor definitions.
R_Init: Init Doom refresh subsystem.
DecalLibrary: Load decals.
PWO_Init: Initializing preferred weapon order.
M_Init: Init menus.
P_Init: Init Playloop state.
ParseSBarInfo: Loading default status bar definition.
ParseSBarInfo: Loading custom status bar definition.
D_CheckNetGame: Checking network game status.
using alternate port 10666
player 1 of 1 (1 nodes)
Initializing network subsystem.
Server using alternate port 10666.
Winsock initialization succeeded!
IP address 169.254.56.226:10666
GeoIP initialization failed.
UDP Initialized.
NAT discovery error: Fail to find an UPNP NAT.
*** MAP01: entryway ***
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