If you do not want to share a Delivery that has been previously shared to an external recipient (as described in Share a Delivery), you can revoke access to that Delivery as follows:
Open the relevant Delivery record
In the Delivery details panel, navigate to the Shares tab
Hover over the email address of the relevant external recipient
Click the Delete button next to the recipient’s email address.
In the Delete confirmation pop-up window, click the Delete button
You'll see a ✓ Record Deleted confirmation message appear (bottom left). The share link is deactivated and access to that Delivery is revoked immediately for that recipient. The Delivery record is not "deleted" per se and is still accessible to you as an Interu user.
If the external recipient then tries to access that Delivery using the method described in Share a Delivery, when they click in the first email (as described in Open Shared Delivery Link), they will land on a 404 error page and a ! The selected resource could not be found error message will appear (bottom left):
