This error occurs when the in-game shop is currently closed.

エラーメッセージ「The bank is being used by another member of the Warband」が表示された場合の対処方法

Troubleshooting steps for resolving network problems in World of Warcraft. 

SC2をすでに購入している場合でも、SC2の購入を求められる理由に関する情報。

Refund policy for Heroes of the Storm in-game purchases.

Lord of Destructionは拡張版であり、ディアブロⅡを先に購入する必要があります

Steps on how to reduce the size of your Heroes of the Storm Installation

Black Screen when starting StarCraft II.

Heroes of the Stormの進行状況に関する情報

What to do if you want to swap the names between two of your characters.