[.net] How to go about deleting files within a directory?

Here's an example.

Thank you!

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;

namespace DeletingFiles
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{
string path = @"C:\Documents and Settings\Administrator\Local Settings\Application Data\Mozilla\Firefox\Profiles\8lrj220l.default\Cache";
string target = @"C:\Documents and Settings\Administrator\Local Settings\Temporary Internet Files";

try
{
if (Directory.Exists(target))
{
label1.Text = "IE has: " + Directory.GetFiles(target).Length.ToString();
foreach (string filename in System.IO.Directory.GetFiles(target, "*.gif"))
{
System.IO.File.Delete(filename);
}
}

if (Directory.Exists(path))
{
label1.Text += "\nFireFox has: " + Directory.GetFiles(path).Length.ToString();
}

}
catch (Exception)
{
label1.Text = "The process failed.";
}
finally { }
}
}
}

Files still there. Or else I deleted something else by accident. ;x

It seems to work if I change the directory. What kind of problem could I be having with the temporary internet files directory for ie? I am logged in as administrator.