Appending to a file using C#
<pre><code> StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/abc.txt"));
Stream stream1 = await file.OpenStreamForWriteAsync();
StreamWriter sr1 = new StreamWriter(stream1);
</code></pre>

<p>It worked fine with StreamReader.
It had an exception saying </p>

<pre><code>   Access denied due to security concerns.
</code></pre>

<p>How to correct this code?
Thanks in advance.</p>
