Symptoms: Users report that on some views in a SharePoint 2010 document library or list, the export process results in an Excel table with the first column missing. Additionally, the first column in the table is Content Type, regardless of the view’s original column order. No error is reported by the application. Users of Excel 2007 are able to export the list without missing data and without errors.
Cause: Bug. Possibly because Excel 2010 is not able to sucessfully convert the object data in the Content Type field to text.
Resolution: Remove the Content Type field from the columns to be displayed in the view. (Switch to the view>Modify View> uncheck the box next to the field “Content Type”>OK). Note that you will still be able to filter, but not sort, the results by Content Type, even if the Content Type field is not displayed.