1. Add message board portlet to the page
2. Click 'add category'
3. Click into the new category
4. Click 'post new thread'
5. Enter subject and body content
6. Click 'attach files' and select a file.
7. Export community LAR, flagging all selections
8. Create new community and import the LAR file, flagging all selections
When you return to the message board and click to the thread, no attachment can be found.