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If your financial institution is listed under the Already Set Up tab but you are still unable to download by clicking the Update All Accounts button or menu item, then you may need to deactivate this (non-working) account and then return to the Set Up Transaction Download view to reconnect. (You can deactivate downloads for an account by going to the account register, clicking the Settings icon in the bottom right corner, and unchecking the "I want to download transactions" option on the Account Settings sheet.)