Note: This report will only appear under the 'Delivery' section of a campaign's reporting overview page if you have external dynamic content enabled in your account, you have used it within your campaign and if any requests for external dynamic content for contacts return no content (an HTTP 204 status code).
If your campaign uses external dynamic content in it but a request for external dynamic content for a contact returns no content (an HTTP 204 status code), the contact is skipped while sending to the rest of the contacts continues. Any skipped contacts are recorded in the 'Email skipped' report, which will appear under the 'Delivery' section of your campaign's reporting overview page.
Making use of the 'Emails skipped' report
This report displays all of the recipients who were skipped and thus didn't receive the campaign because the request for external dynamic content for the contact returned no content.
Clicking on the Display button will enable you to change the view of this report.
Clicking on Export next to it will provide options to either export the contacts list into a CSV file or create a new address book with them.
To view the drill down detail on other reports, use the More reports... button located next to the title of the report. This will provide a menu from which you can select the report type as shown below: