XP中umsd如何安装？安装总是提示要插入USB插槽。

protected void Linkadd_Click(object sender, EventArgs e)
{
Insertclass();
}
protected void GridView2_SelectedIndexChanged(object sender, EventArgs e)
{
string id = this.GridView2.SelectedDataKey["Classid"].ToString();

OleDbConnection con = db.con();
con.Open();
OleDbCommand cmd = new OleDbCommand("select * from JiaoyanshiClass where Classid=@Classid", con);

cmd.Parameters.Add("@Classid", SqlDbType.VarChar);
cmd.Parameters["@Classid"].Value = id;
OleDbDataReader sdr = cmd.ExecuteReader();
if (sdr.Read())
{
this.txtjieci.Text = sdr["Ctime"].ToString();
this.txtjieshu.Text = sdr["CweekEndTime"].ToString();
this.txtlaoshi.Text = sdr["Cteacher"].ToString();
this.txtname.Text = sdr["Cname"].ToString();
this.txtweek.Text = sdr["Cdate"].ToString();
this.txtxi.Text = sdr[&q