The invision community system sets up emails via the email template system. This gives you the ability to amend the email structures from within your ACP, without the need to edit any core files.
The following guide shows how the Email Template system works, and where you would be looking in order to change a particular email.
Email Structure
The email template structure is made up of 4 parts, in which you would need to be aware of to make changes to your emails.
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