backup in sql experess

چطور از اس کیو ال اکسپرس ریستور کنبم؟

این کد بک آپش:
ریستور رو ندارم:

private void button1_Click(object sender, EventArgs e)
{
string strFileName = "BackupFile.bak";
try
{
this.Cursor = Cursors.WaitCursor;
SqlCommand cmd = new SqlCommand();
SqlConnection.ClearAllPools();
cmd.Connection = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=G:\Users\Moha mmad\Documents\Sandwech.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True;");
cmd.Connection.Open();
string dbname = cmd.Connection.Database;
cmd.Connection.Close();
string query = "BACKUP DATABASE [" + dbname + "] TO DISK ='D:\\" + strFileName + "' WITH NO_COMPRESSION ,CONTINUE_AFTER_ERROR ,FORMAT, INIT, NAME = N'accounting-Full Database Backup', SKIP,NOREWIND, NOUNLOAD, STATS = 10";
cmd.Connection = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=G:\Users\Moha mmad\Documents\Sandwech.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True;");
cmd.Connection.Open();
cmd.CommandText = query;
cmd.ExecuteNonQuery();
cmd.Connection.Close();
this.Cursor = Cursors.Default;
MessageBox.Show("تهیه نسخه پشتیبان از اطلاعات با موفقیت انجام شد", "پشتیبان گیری", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch (Exception ex)
{
MessageBox.Show("Error Occurd : " + ex.Message);
}
}