Please change the second uploader code to:

 

  <%
    Dim uploader2
    Set uploader2=new AspUploader
    uploader2.MaxSizeKB=10240
    uploader2.Name="myuploader2"
    uploader2.InsertText="Archivos"
    'uploader2.MultipleFilesUpload=true
    uploader2.AllowedFileExtensions="*.doc,*.pdf"   
    'uploader2.SaveDirectory="img"   
    uploader2.ManualStartUpload=true
 %>
 <%=uploader2.GetString() %>