Hello, can anyone tell me what I am supposed to do with this code to make it work?

I already have the web.config and sql setup but I everytime I try creating a file with only that code it displays on ie as text. Thanks for the help!

Option Strict On
Imports System.Data
Imports System.Configuration
 
Public Class _404Handler
    Inherits System.Web.UI.Page
 
#Region " Web Form Designer Generated Code " 
#End Region
 
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As _
                 System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
        Try
            Dim strQuery As String = Request.ServerVariables("QUERY_STRING")
            If strQuery <> "" Then
                'Now we'll remove the stuff we don't need.
                strQuery = strQuery.Replace("404;http://", "")
                'Get rid of the domain name since we're dealing with multiple domains.
                Dim intSlashPosition As Integer = strQuery.IndexOf("/")
                strQuery = strQuery.Remove(0, intSlashPosition)
                ' now do a lookup in our table to find out if there is a related page.
                Dim NewURL As Integer = DoURLLookup(strQuery)
                If NewURL <> -1 Then
                    Response.Redirect("/DesktopDefault.aspx?TabID=" & NewURL.ToString)
                Else
                    'if we don't have any, just send them to the home page of the site.
                    Response.Redirect("/")
                End If
            Else
                Response.Redirect("/")
            End If
        Catch ex As Exception
            Response.Redirect("/")
        End Try
    End Sub
    
    'This function performs the lookup in the database to find a related page for the broken link.
    Function DoURLLookup(ByVal inURL As String) As Integer
        Dim cnn As New SqlConnection(ConfigurationSettings.AppSettings("connectionString").ToString)
        Dim myCommand As SqlCommand = New SqlCommand("SELECT NewTabID FROM " & _
             "NotFoundLookup WHERE OldURL = '" & Replace(inURL, "'", "''") & "'", cnn)
        cnn.Open()
        Dim result As SqlDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection)
        If result.Read Then
            Dim TabID As Integer = CType(result("NewTabID"), Integer)
            cnn.Close()
            Return TabID
        Else
            cnn.Close()
            Return -1
        End If
    End Function
 
End Class

It sounds like your web server isn't set up to handle ASP.NET pages, or that you are using the wrong extention. ASP.NET pages need to have the extention .aspx
Other than that, make sure the .NET framework is installed on the server.

So if I copy the code and paste it into notepad and call it redirect.aspx, it should work right? I can't get it to do anything but display text.

It should do if your server is set up correctly. If it doesn't, check that the server has the .NET Framework installed on it