Error deserializing an XML file using an XSD schema in Vb.Net

When I try to read the contents of an XML file with a schema XSD using the following Vb.Net ...

Dim Serializador As New XmlSerializer(GetType(Esquemas.aemps_prescripcion_envases))
Dim FileName As String = Path.Combine("N:\Nomenclator", "DICCIONARIO_ENVASES.xml")
Dim fs As New FileStream(filename, FileMode.Open)
Dim psEnvases As Esquemas.aemps_prescripcion_envases = CType(Serializador.Deserialize(fs), Esquemas.aemps_prescripcion_envases)

... I always get the following error:

  

Not expected http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases'>.*

I have generated the corresponding C # class using the xsd / c ...

using System.Xml.Serialization;
/// <comentarios/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType=true, Namespace="http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases")]
[System.Xml.Serialization.XmlRootAttribute(Namespace="http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases", IsNullable=false]
public partial class aemps_prescripcion_envases {
    private aemps_prescripcion_envasesEnvases[] itemsField;  
    /// <comentarios/>
    [System.Xml.Serialization.XmlElementAttribute("envases")]
    public aemps_prescripcion_envasesEnvases[] Items {
        get {
            return this.itemsField;
        }
        set {
            this.itemsField = value;
        }
    }
}
/// <comentarios/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType=true, Namespace="http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases")]
public partial class aemps_prescripcion_envasesEnvases {
    private string codigoenvaseField;
    private string envaseField;
    /// <comentarios/>
    public string codigoenvase {
        get {
            return this.codigoenvaseField;
        }
        set {
            this.codigoenvaseField = value;
        }
    }
    /// <comentarios/>
    public string envase {
        get {
            return this.envaseField;
        }
        set {
            this.envaseField = value;
        }
    }
}

The XML file has the following content:

<?xml version="1.0" encoding="UTF-8"?>
<aemps_prescripcion_envases xmlns="http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases" xsi:schemaLocation="http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases http://schemas.aemps.es/prescripcion/aemps_prescripcion_envases.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <envases>
    <codigoenvase>1</codigoenvase>
    <envase>Ampolla</envase>
  </envases>
  <envases>
    <codigoenvase>2</codigoenvase>
    <envase>Aplicador</envase>
  </envases>
....
</aemps_prescripcion_envases>

How is this solved?