Get error when crystal report image get from file path

I want to show an image in my Crystal report by image file path, but get an error “FileNotFoundException was unhandled”. I have verified the file exists at the specified path. Any suggestion to solve my problem? Hope you can understand my question.

 private void btndefault_Click(object sender, EventArgs e)
    {
        ImagePathLoc = @"C:/Temp/default.jpg";
        FileStream fstream = new FileStream("default.jpg",FileMode.Create);
        imgbyte = new byte[fstream.Length];
        fstream.Read(imgbyte, 0, Convert.ToInt32(fstream.Length));
        fstream.Close();

        ImageData ds = new ImageData();
        DataRow drNew = ds.Tables[0].NewRow();
        drNew["Image"] = imgbyte;
        drNew["Name"] = "default.jpg";
        ds.Tables[0].Rows.Add(drNew);

        crystalReportViewer1.ShowExportButton = true;
        crystalReportViewer1.ShowPrintButton = true;
        string mApppath = Application.StartupPath;

        crReportDocument = new CrystalReport1();
        crReportDocument.SetDataSource(ds.Tables[0]);
        crystalReportViewer1.ReportSource = crReportDocument;
    }