How To Reset DNS Zone files to the defaults:
And “Advanced Zone Editor” under the “Domains” Category in cPanel.
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1. Select a domain from the drop-down menu.
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2. Click “more” at the Reset Zone File part.
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3. Tick the check box next to “Are you sure you want to erase all entries and revert to the default state”?
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4. Click “Reset Zone File”.
If you are looking at How to Add A DNS record in Advanced DNS Zone files. Feel free to click here!