I have Special XML file with `utf-16` encoding type. this file used to store data and I need to Edit it Using C# windows forms Application

```
<?xml version="1.0" encoding="utf-16"?>
<cProgram    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" ID="b0eb0c7e-f4de-4bc7-9e62-7a086a8c2fn8" Version="16.01" xmlns="cProgram">
  <Serie>N    </Serie>
  <No>123456</No>
  <type>101</type>
  <Dataset4>larg data here 2 million char</Dataset4>
</cProgram>123456FF896631N    4873821012013-06-14

```

the problem is: it is not ordinary XML file
Because at the very End of the file I have a string line too, and that would give this error 

```
Data at the root level is invalid. Line x, position x

```

when I try to load it as xml file

I tried to temporary replace the last line and get it back after I change the inner text, and it works But I lost the declaration Line and I didn't find a way to rewrite it when I have that text at the end of the file !\_  

so I need to change the `InnerText` of (Serie) and (No) nodes 
but I don't Want to lose the declaration Line or the string text at the end of the file