User uploads files in SalesForce. But it should actually save to SharePoint. User will not be knowing that, file is being saved in SharePoint and Only the Reference to the files will be in Salesforce.
After save, he can access all these files and when he clicks the file, it should pull the data from SharePoint and display it for him.
i have already gone through these links: http://goldeninsights.com/2011/02/24/getting-sharepoint-to-talk-to-salesforce-on-the-cheap-part-1/#comment-6620
But my client is not ready for this solutions as there seems to be no security.