Printer don't print greek characters

Question

What i'm trying to do is to read a .txt file and sent it to printer. The problem is that the printer normally print the latin alphabet characters but replace the greek characters with ???. I'm really new to C# programming so if anyone could help it will
be realy thankfull. I use windows 7 ultimate 64-bit and microsoft visual studio 2013. My code is:
System.IO.StreamReader fileToPrint;
System.Drawing.Font printFont;
private void printButton_Click(object sender, EventArgs e)
string printPath = System.Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
fileToPrint = new System.IO.StreamReader(printPath + @"\myFile.txt");
printFont = new System.Drawing.Font("Arial", 10);
printDocument1.Print();
fileToPrint.Close();
private void printDocument1_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
float yPos = 0f;
int count = 0;
float leftMargin = e.MarginBounds.Left;
float topMargin = e.MarginBounds.Top;
string line = null;
float linesPerPage = e.MarginBounds.Height/printFont.GetHeight(e.Graphics);
while (count < linesPerPage)
line = fileToPrint.ReadLine();
if (line == null)
break;
yPos = topMargin + count * printFont.GetHeight(e.Graphics);
e.Graphics.DrawString(line, printFont, Brushes.Black, leftMargin, yPos, new StringFormat());
count++;
if (line != null)
e.HasMorePages = true;

Answer 1

Thanks for the quick replay it worked with: 
fileToPrint = new System.IO.StreamReader(printPath + @"\myFile.txt", Encoding.Default);