Wired or WIFI connection? Tried in both, with different computers.
When the error occurs/How often? Often but again, not all threads, the ones I listed are weeks old now and I still can't see them.
Is a VPN being used when this occurs? Nope.
What ISP Is being used? Claro NXT Telecomunicacoes Ltda


More examples of threads not accessible:

https://forum.square-enix.com/ffxiv/...een-a-few-days
https://forum.square-enix.com/ffxiv/...-Police-CIA%29
https://forum.square-enix.com/ffxiv/...es-or-knows-it.