When a sheet that has a new line in a text value is exported and the resulting file is opened in Excel, the value is displayed without a new line. If you enter edit mode and then exit (without confirming the value by pressing enter) the new line will appear. The reason for this behavior is that when there is a new line in a text value Excel automatically applies wrap text on the cell while RadSpreadsheet does not do that. A possible workaround is to apply wrap text on new values with new line in them.