Yes, you can delete the attachments after uploading them using the Mass File Upload app. Follow the steps below:
Steps to Follow:
- Upload Attachments:
- Use the List View, Search, or Advanced SOQL option to upload attachments.
- Receive Success Message:
- After successfully uploading attachments, a success message will appear on the rendered table.
- Click on the Delete Button:
- In the same table, look for the Delete button, and click on the "Delete" button.

- In the same table, look for the Delete button, and click on the "Delete" button.
- Confirm Deletion:
- A confirmation pop-up will appear. Click "OK" to confirm.

- A confirmation pop-up will appear. Click "OK" to confirm.
- Deletion Complete:
- Once you click "OK," all attachments will be deleted from the records.
PS: View Mass File Upload, Salesforce file upload app on Salesforce AppExchange: https://appexchange.salesforce.com/appxListingDetail?listingId=82cf236b-1ee8-4ea7-aebf-fd0c89fb93bd