Whether you are able to edit the entire set of source code for a template is reliant on just one factor, whether or not you started with a Fully Unlocked version of the template. In the case that you started with a "fully unlocked' template, you can click the Source button in the email editor toolbar in order to see a full HTML version of your template. However, if you started with a normal template, you will only be able to edit the HTML of each element on your template in a section (div) by section basis. If you need to gain access to the underlying HTML for that template, you will need to recreate it using a "fully unlocked" version of that layout from our Design Your Own template area.
Can I edit the HTML source of an email template in Core iQ?
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