Reading a text file using C#

[DJ_Catboy]

Hi,

I may be completely stupid but I can't make the code below work?! The text file TEST.TXT is a one liner (attached) and it is still not working!!!!! Please can somebody help me...... this was copied straight from MSDN...

using (StreamReader sr = new StreamReader("c:\\TEST.TXT")) 
{
String line;
while ((line = sr.ReadLine()) != null) 
{
tb.AppendText(line + Environment.NewLine);
}
}

I receive the error as follows:

Index and Length must refer to a location within the string.

Does anybody know what I am doing wrong?

Thanks in advance,
DJ