Problem with using textBox and highlight, ini highlighter is missing


I'm not an expert, but if I use a textBox (metroTextBox) the tags will shown on begin and end from the file. I use an ini file and in your project file I couldn't find it for ini file.

I see following, the ini file was loaded with StreamReader
Result from textBox:
<div style="color:Black;background-color:White;"><pre>
...Content from ini file...
The first and the third line are not in the ini file and I don't need it to the output, where is the issue and how can it fixed?

Thank you in advance.