I'm not sure if this will help, but I have some "attachments," and here's how to delete those:
- Go to "Settings" (near the top right of the window on a normal forum page)
- On the left side of the screen, there's a series of menu picks. Scroll down to near the bottom where it says "Attachments"
- A list of attachments will pop up, each of which will have a check box to the right of it. You can check boxes and then scroll to the bottom and hit the "Delete Selected" button.