I have an excel file set up to pull data from SQL Server 2008R2. I can view it and refresh it fine locally in Excel 2010.
I upload it to SharePoint 2010 and can view the data in the spreadsheet in the browser using Excel Services. However, when I click to refresh the data in the spreadsheet in the browser (clicking Data > Refresh All), the data does not get refreshed. One thing to note is that when I do open up the excel spreadsheet in the browser it shows this message: