If you wish to have user(s) informed whenever a detail is changed on any of your Bank Accounts or Payment Gateways you can set up this feature.
Under Setup > System Wide Settings in the Organisation Settings area you can set the Finance Administrator Email field.
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Upon any change in the Bank Accounts and Payment Gateway section you will be immediately sent an email
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This email will contain a PDF attachment outlining the change to what account, by who, and what the change was.
This feature is helpful for security and auditing control purposes.