Hi and thanks for your answer,
I used to be under v25, i just tried to upgrade to v27 but it did not work, same message...
Does the error still appear when you add the line to bitcoin.conf? It should be an error that is associated with upnp instead of Bitcoin Core. Is the portmapping error the final line before Bitcoin Core closes?
Hello and thanks for your answer,
Sorry but i'm not very familiar with modifiying BitcoinCore so i don't know what you mean by "adding the line to bitcoin.conf