Sophos for Microsoft SharePoint: SharePoint 'Discussion board' displays duplicate entries for item

Issue
The SharePoint 'New-Discussion board' displays multiple entries for a single item. This happens when you upload a discussion group item which has an attachment which has itself been blocked.

When an item is added to a SharePoint discussion board and the attachment is blocked by Sophos for Microsoft SharePoint, the item appears without the attachment, i.e. the attachment itself is correctly blocked. However, multiple entries may be created and displayed for the same item when the item is added under one of the following circumstances: 

• directly using the SharePoint web interface, using 'New-Discussion board' (you may see an error message displayed in the web page in this case)
• when you submit an entry by email.

This is a known Microsoft SharePoint issue.