dataGridView1.Rows[x1].Cells[y1].Style.BackColor = System.Drawing.Color.Red; System.Threading.Thread.Sleep(1000);
İ want to wait one second before
Is it pausing, but you don't see your red color appear in the cell? Try this:
dataGridView1.Rows[x1].Cells[y1].Style.BackColor = System.Drawing.Color.Red; dataGridView1.Refresh(); System.Threading.Thread.Sleep(1000);