I used to use DeSmume to play my Nintendo DS Online games or make some Pokémon trades with my DS cartridges (I'm even the person who uploaded these two videos: ) I avoided using MelonDS because it was horrible for weak PCs, my PC only had 4 GB of RAM on an Intel Celeron without a video card so I preferred to continue on DeSmume as I was able to play on it.
But recently I switched PCs, although it is still not so good now it is an i3 with 8 GB of RAM, so I thought about testing MelonDS again since it still receives updates unlike NO $ GBA and DeSmume, the performance this is much better than when I tested it at the time, but I had a problem playing online:
In Pokémon White 2 using AltWFC:
Error Code: 20100 Unable to connect to Nintendo Wi-Fi Connection.
In Metroid Prime Hunters with Wiimmfi:
Error Code: 20100 Unable to connect with this Nintendo WFC ID
In Mario Kart DS:
Nintendo WFC service for this software has been halted
I did all the steps correctly and I even can pass the WFC Connection test without any problems so I'm not sure what's going on here, could someone help me?
But recently I switched PCs, although it is still not so good now it is an i3 with 8 GB of RAM, so I thought about testing MelonDS again since it still receives updates unlike NO $ GBA and DeSmume, the performance this is much better than when I tested it at the time, but I had a problem playing online:
In Pokémon White 2 using AltWFC:
Error Code: 20100 Unable to connect to Nintendo Wi-Fi Connection.

In Metroid Prime Hunters with Wiimmfi:
Error Code: 20100 Unable to connect with this Nintendo WFC ID

In Mario Kart DS:
Nintendo WFC service for this software has been halted

I did all the steps correctly and I even can pass the WFC Connection test without any problems so I'm not sure what's going on here, could someone help me?