Mass delete attachments with Salesforce Data Loader

This article explains how to mass delete attachments for an object using Salesforce Data Loader.

Export the Attachments to Delete

1. Perform a Data Export for the Attachment object that you wish to delete:

   In Salesforce Classic: Setup | Data Management | Data Export
   In Lightning Experience: Setup | Data | Data Export

   Note: Make certain you select the Include attachments/documents checkbox (including attachments/documents may significantly slow down and enlarge your export).

Prepare the Delete File

2. Take the original Data Export file called "Attachment.csv."
3. Remove all rows/attachments that you do not want to delete.
4. Remove all columns except Id.
5. Save the modified CSV as delete_attachment.csv.

Run the Delete in Data Loader

6. Log in to Data Loader.
7. Select the Delete option.
8. In Step 2, select the Show all Salesforce Objects checkbox; select Attachments; then click the Browse button, select delete_attachment.csv, and click Next.
9. In Step 3, click Create or Edit a Map and then Auto-Match Fields to Columns. This matches the column header (Id) to your database. Click OK to proceed. Back on the Step 3 Mapping window, click Next. For more, see Define Data Loader Field Mappings.
10. Specify the directory in Step 4 that will house your Data Loader Success and Error files. This can be any folder on your computer. After specifying the directory, click Finish.
11. You'll be prompted with a "Yes or No" pop-up to confirm the Delete action. Click Yes. Data Loader will then attempt to delete your Attachments on each of the row records. This process can take a while depending on the size and number of attachments. You'll see an Operation Finished pop-up when the process completes.