Help about the HRESULT:0x800A0259 COMException in C# InnerHtml

See more:

C#

C#4.0

Hi every one,

I made a winform application with C# 2010 Express. I used the webbrowser, and I plan to analyze one web page and update the content in that page.

However, I got the div element <textarea id="articleText"></textarea>, when I start to fill in that div, I got the 'HRESULT:0x800A0259 COMException' error.

I have no ideal about that error, could any one help me, thanks a lot...

Following is the error code:

HtmlElementCollection dhl = webbrowser1.Document.GetElementsByTagName("textarea");
for (int i = 0; i < dhl.Count; i++)
{
htmlElement item = dhl[i];
if (item.GetAttribute("id").Equals("articleText"))
{
    item.InnerHtml = "<font color='red'> Here is the content...</FONT><br><br>";  
    .....
}

The error happens on

item.InnerHtml = "<font color='red'> Here is the content...</FONT><br><br>"; 

However, if I changed the item.InnerHtml = "content", there is no error.

I'm very strange about the problem.