No problem! There are many little things you don't know until you try :P

You should check with the bank/issuer of your Visa debit card though just to make sure they don't charge foreign transaction fees or any other fees! Simple doesn't charge any fee on their side, but Visa does and I didn't find out until after I withdraw cash (I sort of expected it to happen, but you never know).

Reference for Japan Post ATMs: http://www.jp-bank.japanpost.jp/en/i...ias_index.html

Enjoy your trip!