I am using the PrintDocument class to print to my Brother label printer. When I execute the Print() method, the printer starts flashing a red error light, but everything else returns successful.

I can run this same code on my laser printer and everything works fine.

How can I see what is causing the error on my label printer?

Code:

public class Test
{
    private Font printFont;
    private List<string> _documentLinesToPrint = new List<string>();

    public void Run()
    {
        _documentLinesToPrint.Add("Test1");
        _documentLinesToPrint.Add("Test2");
        printFont = new Font("Arial", 10);
        var pd = new PrintDocument();
        pd.DefaultPageSettings.Margins = new Margins(25, 25, 25, 25);
        pd.DefaultPageSettings.PaperSize = new PaperSize("Label", 400, 237);

        var printerSettings = new System.Drawing.Printing.PrinterSettings();
        printerSettings.PrinterName ="Brother QL-570 LE";
        pd.PrinterSettings = printerSettings;
        pd.PrinterSettings.Copies = 1;
        pd.PrintPage += new PrintPageEventHandler(this.pd_PrintPage);
        pd.Print();
    }

    // The PrintPage event is raised for each page to be printed. 
    private void pd_PrintPage(object sender, PrintPageEventArgs ev)
    {
        float linesPerPage = 0;
        float yPos = 0;
        int count = 0;
        float leftMargin = ev.MarginBounds.Left;
        float topMargin = ev.MarginBounds.Top;
        string line = null;

        // Calculate the number of lines per page.
        linesPerPage = ev.MarginBounds.Height /
           printFont.GetHeight(ev.Graphics);

        // Print each line of the file. 
        while ((count < linesPerPage) && (count < _documentLinesToPrint.Count))
        {
            line = _documentLinesToPrint[count];

            yPos = topMargin + (count *
               printFont.GetHeight(ev.Graphics));
            ev.Graphics.DrawString(line, printFont, Brushes.Black,
               leftMargin, yPos, new StringFormat());

            line = null;
            count++;
        }

        // If more lines exist, print another page. 
        if (line != null)
            ev.HasMorePages = true;
        else
            ev.HasMorePages = false;
    }
}