Not sure how to send unhandled errors to the ErrorPage. ASP.NET VS 2002 SQL Server 2005

Not sure how to send unhandled errors to the ErrorPage

I would like to capture unhandled error information, send a friendly message to the user, and receive a detailed report.

Any help or documentation references would be appreciated.

ErrorPage.aspx

    <h1 style="text-align: center">
        <span style="font-size: 14pt">
        You found an error that I missed&nbsp;
        </span>
    </h1>
    <p>
        <span style="font-size: 12pt">
        Use this page to report the error.&nbsp;
        </span>
    </p>
 
        <table style="font-size: 12pt">
                 <tr>
                <td colspan="3" style="width: 466px">
                <a href="mailto:dmartin@reslinker.com? subject=Error Report& body=I would report the following error:">
                        Send us the error report</a>
                </td>
                <td style="width: 100px">
                    <asp:Button ID="btnSendError" runat="server" Text="Send Report" Width="101px" /></td>
                <td style="width: 100px">
                </td>
            </tr>
            <tr>
                <td colspan="3" style="width: 466px">
                    <asp:TextBox ID="txtErrorMsg" runat="server" Height="34px" Rows="8" TextMode="MultiLine"></asp:TextBox></td>
                <td style="width: 100px">
                </td>
                <td style="width: 100px">
                </td>
            </tr>
        </table>
        <span style="font-size: 14pt"></span>

ErrorPage.aspx/vb

Imports System.Net.Mail
Imports System.Diagnostics
Partial Class ErrorPage
    Inherits System.Web.UI.Page

Protected Sub btnSendError_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSendError.Click
        Dim objClient As New SmtpClient
        Dim objEMail As New MailMessage
        Dim strMsg As String = ""
        Dim strTo As String = ""

        'Dim ErrorMessage = "The error description is as follows : " & Server.GetLastError.ToString
        Dim ErrorMessage As String = ""
        If Not Server.GetLastError Is Nothing Then
            ErrorMessage = "The error description is as follows : " & Server.GetLastError().InnerException.ToString()
            Me.txtErrorMsg.Text = ErrorMessage
        End If

        strTo = "dovberman@cableone.net"
        'objClient.Host = "localhost"
        objClient.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory
        objClient.PickupDirectoryLocation = "C:\Inetpub\mailroot\Pickup"
        objEMail.To.Add(New MailAddress("dmartin@reslinker.com"))
        objEMail.From = New MailAddress("dovberman@cableone.net")
        objEMail.Subject = "My Stock Picker Error Report"
        objEMail.Body = ErrorMessage
        Try
            objClient.Send(objEMail)
            Response.Write("Your E-mail has been sent sucessfully")

        Catch exc As Exception
            Response.Write("Send failure: " + exc.ToString())
        End Try
    End Sub