Sharepoint 2013 and Excel 2013 PowerView

I have a problem when creating a report via Excel 2013 using PowerView connecting to a SSAS 2012 Tabular instance I can see the data correctly in Excel 2013. But when I upload that same report to a Sharepoint 2013 PowerPivot Gallery and hit"Create Power View Report" I get the error "Server not Found" as below. The connection has been defined in the Excel file is there anywhere else the connection needs to be defined within Sharepoint 2013? Any help will be appreciated..

Thanks...