Form this you can border around a1 row that wise use set border for which cells of table you required by range:
xlRng = xlWorkSheet.Range("a1")
xlRng.EntireRow.BorderAround(Excel.XlLineStyle.xlContinuous, Excel.XlBorderWeight.xlMedium, Excel.XlColorIndex.xlColorIndexAutomatic, Excel.XlColorIndex.xlColorIndexAutomatic)
For more formatting operation you can follow this link:
http://vb.net-informations.com/excel-2007/vb.net_excel_page_format.htm[
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