It is an event it will be called automatically when new rows are added.....
by using the following code u can drop the event and enable the event for row added
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So when datagridview is loaded for the first time make sure to drop the event.soon after loading
enable the even again
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//event Drop
this.dataGridView1.RowsAdded -= new System.Windows.Forms.DataGridViewRowsAddedEventHandler(this.dataGridView1_RowsAdded);
//event enable
this.dataGridView1.RowsAdded += new System.Windows.Forms.DataGridViewRowsAddedEventHandler(this.dataGridView1_RowsAdded);