I always have to ask to go to someone else's town because whenever I try and host at mine I get the blue resetti screen, but with no code, just a message saying an error had occurred. I can visit other towns with no problem. This makes me think I don't have a weak connection as has been suggested before.
Is anyone able to shed any light on this?
If you are going to walk on thin ice...
...You might as well dance
You likely have a built-in firewall enabled on your router preventing others from connecting with you easily. If you know someone who can manage your router settings, or if you're the only one, then I would recommend setting your 3DS to have a Static IP. Then you can put it through DMZ which will avoid having to disable your router firewall. (further steps here)
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