User with journal entry Create rights can delete a journal entry attachment. Deletion of attachments can only occur to unposted journal entries. 

To delete a journal entry:

  1. Navigate to the Journals module.
  2. Double-click the Attachment icon on an unposted journal entry in the header section. 
    The Journal Attachments window opens.
  3. Select the row to be deleted.
  4. Right-click and select Delete.
  5. Select OK to close the Journal Attachments window.