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Follow the steps given below to activate the override functionality for delete and update the attachment in the FTP Attachments related list:
Go to Object Manager, then Open the FTP Attachment object’ Buttons link and Actions
Click on edit of Standard button “Delete”.Select the visual force page “Delete Attachment ENZ_Delete Attachment” . Click on Save
Click on edit of Standard button “Edit”. Select the visual force page “Update Attachment[ENZ_Update Attachment]”. Click on Save
Go to the FTP Attachments® related list and click on delete of any attachment
Click on Delete button of the page shown below:
There will be a message displayed for updating the custom setting
Go to Setup then type “Custom Settings” in the quick find box
Click on the edit of Settings.
Enter the current base URL, and click on save
Go to the FTP Attachments® related list, if you wish to delete any attachment then click on delete and the attachment will be deleted permanently
Go to the FTP Attachments® related list, if yu wish to update the attachment then click on edit and it will take you to the Update page. You can update your file here and click on done after updating the file
Select file to be updated using upload button, Click on attach for updating the file
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