OGC Filter set but symbolizer expected in GeoServer SLD

Question

I have a problem with one of my SLD files and do not know what is causing the problem. The error message is pretty clear: line 18: cvc-complex-type.2.4.a: Invalid content was found starting with element 'ogc:Filter'. One of '{"http://www.opengis.net/sld":Symbolizer}' is expected. However, when I look into the example of the cookbook for attribute based or for zoom based polygons then I cannot figure out why I am getting the error. Have a look at the code below... I don't know why a symbolizer is expected in line 18, even though the example in the cookbook has the structure the same way as I do, or not!

Any suggestions on how to overcome the problem?

I am running Geoserver in version 2.3.2

<?xml version="1.0" encoding="ISO-8859-1"?>
<StyledLayerDescriptor version="1.0.0"
 xsi:schemaLocation="http://www.opengis.net/sld StyledLayerDescriptor.xsd" 
 xmlns="http://www.opengis.net/sld" 
 xmlns:ogc="http://www.opengis.net/ogc" 
 xmlns:xlink="http://www.w3.org/1999/xlink" 
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <NamedLayer>
    <Name>Baggrund NO2</Name>
    <UserStyle>
      <Title>Baggrund NO2</Title>
      <FeatureTypeStyle>
        <Rule>
          <Name>4,75 - 5,31</Name>
          <Title>4,75 - 5,31</Title>
          <MinScaleDenominator>23000</MinScaleDenominator>
          <MaxScaleDenominator>1000000000</MaxScaleDenominator>
          <ogc:Filter>
            <ogc:PropertyIsEqualTo>
              <ogc:PropertyName>Type</ogc:PropertyName>
              <ogc:Literal>1.0000</ogc:Literal>
            </ogc:PropertyIsEqualTo>
          </ogc:Filter>
          <PolygonSymbolizer>
            <Fill>
              <CssParameter name="fill">#1a9641</CssParameter>
              <CssParameter name="fill-opacity">0.40</CssParameter>
            </Fill>
          </PolygonSymbolizer>
        </Rule>
      </FeatureTypeStyle>
    </UserStyle>
  </NamedLayer>
</StyledLayerDescriptor>

Answer 1

Put the MinScaleDenominator and MaxScaleDenominator element after the ogc:Filter element:

<?xml version="1.0" encoding="ISO-8859-1"?>
<StyledLayerDescriptor version="1.0.0"
   xsi:schemaLocation="http://www.opengis.net/sld StyledLayerDescriptor.xsd" 
   xmlns="http://www.opengis.net/sld" 
   xmlns:ogc="http://www.opengis.net/ogc" 
  xmlns:xlink="http://www.w3.org/1999/xlink" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <NamedLayer>
    <Name>Baggrund NO2</Name>
    <UserStyle>
      <Title>Baggrund NO2</Title>
      <FeatureTypeStyle>
        <Rule>
          <Name>4,75 - 5,31</Name>
          <Title>4,75 - 5,31</Title>             
          <ogc:Filter>
            <ogc:PropertyIsEqualTo>
              <ogc:PropertyName>Type</ogc:PropertyName>
              <ogc:Literal>1.0000</ogc:Literal>
            </ogc:PropertyIsEqualTo>
          </ogc:Filter>
          <MinScaleDenominator>23000</MinScaleDenominator>
          <MaxScaleDenominator>1000000000</MaxScaleDenominator>
          <PolygonSymbolizer>
            <Fill>
              <CssParameter name="fill">#1a9641</CssParameter>
              <CssParameter name="fill-opacity">0.40</CssParameter>
            </Fill>
          </PolygonSymbolizer>
        </Rule>
      </FeatureTypeStyle>
    </UserStyle>
  </NamedLayer>
</StyledLayerDescriptor>

Order matters in a SLD file in order to validate and GeoServer is quite strict in validation.