Hello guys,
I have a form in which students need to upload files, but when performing the process it is giving the error:
Maximum request size exceeded.
The same happens when I try to download the file (DataGrid1_ItemCommand)
Below is the html and VB code.
HTML: 
<%@ Page Title="" Language="VB" MasterPageFile="~/candidato/MasterPage.master" AutoEventWireup="false" CodeFile="cadMeusDadosAnexos.aspx.vb" Inherits="candidato_cadMeusDadosAnexos" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
    <style>
        .imgDoc {
              max-height:100px;
              max-width: 100px;
        }
    </style>
    
    <ajaxToolkit:ModalPopupExtender ID="mpeAlerta" runat="server" PopupControlID="panAlerta" TargetControlID="BtnAlertaOculto" CancelControlID="BtnCancelaAlerta" BackgroundCssClass="fundo-fosco" DropShadow="true">
    </ajaxToolkit:ModalPopupExtender>
    <div style="display:none;">
        <asp:Button ID="BtnAlertaOculto" runat="server" Text="Abre alerta" />
    </div>
    <div>
        <asp:Panel ID="panAlerta" runat="server" CssClass="alert alert-danger" style="padding:10px !important; max-width:300px !important; display:none;" >
            <div class="h3">ATENÇÃO!</div>
            <hr />
            <div>Por favor, preencha o(s) campo(s) em destaque.</div>
            <hr />
            <div>
                <asp:Button ID="BtnCancelaAlerta" runat="server" CssClass="btn btn-danger" Text="OK" />
            </div>
        </asp:Panel>
    </div>
    <div class="form-group">
        <div class="row">
            <div class="col-sm-12">
                <div><h3>Anexos</h3></div>
            </div>
        </div>
        <div class="row">
            <div class="col-sm-12">
                <div><asp:HiddenField ID="hfID" runat="server" /></div>
                <div><asp:HiddenField ID="hfValida" runat="server" /></div>
                <div class="alert alert-info">
                    <asp:Label ID="LbPessoa" runat="server" Text="LbPessoa" ></asp:Label>
                </div>
                <div style="padding:10px 0px 10px 0px;">
                    Anexe apenas arquivos com extensões .pdf, .jpg ou .jpeg.</div>
                <div style="padding:5px;">
                    <div>
                        <asp:DataGrid ID="DataGrid1" runat="server" AutoGenerateColumns="False" CssClass="btsGrid">
                            <AlternatingItemStyle CssClass="btsGrid-alternate" />
                            <Columns>
                                <asp:BoundColumn DataField="ID" HeaderText="ID"></asp:BoundColumn>
                                <asp:TemplateColumn HeaderText="TIPO DE DOCUMENTO">
                                    <ItemTemplate>
                                        <div style="padding:10px 0px 10px 0px;">
                                            <asp:Panel ID="gpanCampos" runat="server" CssClass="panel-control-transparent" >
                                                <div><asp:Label ID="gLbNomeTipoDoc" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.NOME") %>'></asp:Label></div>
                                                <div><asp:FileUpload ID="gFileUpload1" runat="server" CssClass="form-control" Visible='<%# DataBinder.Eval(Container, "DataItem.VERUPLOAD") %>' /></div>
                                                <div><asp:Label ID="gLbNomeArquivo" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.ARQUIVO") %>'></asp:Label></div>
                                                <div><asp:Label ID="gLbCaminhoArquivo" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.CAMINHODOARQUIVO") %>' Visible="False" ></asp:Label></div>
                                                <div><asp:Label ID="gLbMensagemAnexos" runat="server" ></asp:Label></div>
                                                <div><asp:HiddenField ID="gHfID" runat="server" Value='<%# DataBinder.Eval(Container, "DataItem.ID") %>' /></div>
                                                <div><asp:HiddenField ID="ghfIDImagem" runat="server" Value='<%# DataBinder.Eval(Container, "DataItem.IDIMAGEM") %>' /></div>
                                                <div><asp:HiddenField ID="ghfObrigatorio" runat="server" Value='<%# DataBinder.Eval(Container, "DataItem.OBRIGATORIO") %>' /></div>
                                                <div><asp:HiddenField ID="ghfTestaImagem" runat="server" Value='<%# DataBinder.Eval(Container, "DataItem.TESTAIMAGEM") %>' /></div>
                                            </asp:Panel>
                                        </div>
                                    </ItemTemplate>
                                </asp:TemplateColumn>
                                <asp:TemplateColumn HeaderText="IMAGEM BANCO">
                                    <ItemTemplate>
                                        <div style="padding:10px 0px 10px 0px;">
                                            <asp:Image ID="gImage" runat="server" CssClass="imgDoc" />
                                            <asp:ImageButton ID="gBtnVerImg" runat="server" CommandName='<%# "verImagem" %>' ImageUrl="~/imagens/BtnConsulta.png" />
                                        </div>
                                    </ItemTemplate>
                                    <HeaderStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" />
                                    <ItemStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" />
                                </asp:TemplateColumn>
                                <asp:TemplateColumn>
                                    <ItemTemplate>
                                        <div style="padding:10px 0px 10px 0px;"><asp:CheckBox ID="gCbDelete" runat="server" Visible='<%# DataBinder.Eval(Container, "DataItem.VERIMGDOC") %>' /></div>
                                    </ItemTemplate>
                                    <HeaderStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" />
                                    <ItemStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" />
                                </asp:TemplateColumn>
                            </Columns>
                            <HeaderStyle CssClass="btsGrid-header" />
                        </asp:DataGrid>
                    </div>
                    <div style="margin-top:10px; text-align:center;">
                        <asp:Button ID="BtnEnviar" runat="server" CssClass="btn btn-success" style="margin-right:5px;" Text="Enviar" />
                        <asp:Button ID="BtnExcluir" runat="server" CssClass="btn btn-danger" style="margin-right:5px;" Text="Excluir" />
                        <asp:Button ID="BtnContinue" runat="server" CssClass="btn btn-info" Text="Continue" />
                    </div>
                    <div></div>
                </div>
            </div>
        </div>
    </div>
</asp:Content>
 
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	<location path="UploadPage.aspx">
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Grateful,
Ilano.