Inserts a vertical page break in the worksheet to right of the specified cell.

 public void InsertVerticalPageBreak(Cell rightOfCell)
Public Sub InsertVerticalPageBreak(ByVal rightOfCell As Cell)

A Cell object representing the cell at which to insert a vertical page break.

ws.InsertVerticalPageBreak(ws.Cells["G1"]);
ws.InsertVerticalPageBreak(ws.Cells("G1"))