Web Documents Sharing system

The system will be used to share documents on line, these documents could be one of the following :doc, docs, ppt, xls, or pdf. we have a forum (VBullettin) and we want the users to use the same credentials to upload and download. the project will required a development of a server application (VB.NET), this application will be used to download the uploaded files and scan them from virus( the anti virus will be commercial one, the application will download and update the web site DB for the bad files only and it will not scan the files) so the summary of the project is as the following: upload web application (PHP). download web application (PHP) Virus remover (VB.NET) I will attach two more file to describe the system in more details.