using Html Agility Pack with SharpDevelop

Hello there,

i am pretty new to c# and glad to find Sharpdevelop wich allows to do a bit programming while I do not have admin rights. Great so far.

Now I want to use the html agility pack and installed it.

But in an example System.Web.UI I get a failure. UI is not in the namespace of System.Web. (I try to run the example of htmlagilitypack website)

What do I wrong?

Der Typ- oder Namespacename 'UI' ist im Namespace 'System.Web' nicht vorhanden. (Fehlt ein Assemblyverweis?) (CS0234) - \\HE111180e002\a692517$\Home\Data\SharpDevelop Projects\HTMLLinks\HTMLLinks\MainForm.cs:13,18