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FTP Attachments® comes with a custom link called “Delete” which is used to delete the file in the FTP Attachments® and the actual file from the FTP Server. It is illustrated with the example given below:
Make sure you have already created a custom link Button “Delete” and added it to the FTP Attachments® Layout.
Search for the object to which you have attached file.
Click on the attachment in the FTP Attachments® related list section.
Click on “Delete” link Button in the FTP Attachments® screen. this will open a window with delete and cancel button.
Click on delete, if you willing to delete the file.
Go back to your Salesforce object, and refresh your Salesforce window, the file you have deleted will not be there in the FTP Attachments® related list anymore.
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