Hello Whichi, Thank you for your response.

The 90001 and 90002 errors are connection related errors. This is why we suggest reporting them to your ISP.

Please be aware that Final Fantasy XIV requires a more demanding connection than many other websites and applications. Additionally, your ISP may take you through a certain route to get you to the XIV server and a different route to other websites, meaning you might run into problems with one service but not another simply because of the path your internet chooses to get there.

Hope to be of assistance.