XML + Schema + Namespaces. No matching global declaration available for the validation root

Question

What is the correct syntax when referring to schema when using namespaces?

Problem

Creating an XML document using a given schema.

Error

.xml:9.20: Element '{http://example/buildings/1.0}old_buildings': No matching global declaration available for the validation root.
oldbuildings.xml - invalid
Problem

XML Document oldbuildings.xml

<?xml version="1.0" encoding="UTF-8"?>

<buildings:old_buildings xmlns:buildings="http://example/buildings/1.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://example/buildings/1.0 oldbuildings_schema.xsd">
    <building>
        <name>Name</name>
        <year_built era="BC">2000</year_built>
        <story>...<story>
    </building>
</buildings:old_buildings>

XSD Document schema.xsd:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema targetNamespace ="http://example/buildings/1.0/"
           xmlns:xs        ="http://www.w3.org/2001/XMLSchema"
           xmlns           ="http://example/buildings/1.0/">
    <xs:element name="old_buildings">
        <xs:complexType>
            <xs:sequence>
                <xs:element ref="building"/>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
    <xs:element name="building" type="buildingType"/>
    <xs:complexType name="buildingType">
        <xs:sequence>
            <xs:element name="name"         type="xs:string"/>
            <xs:element name="year_built"   type="yearType"/>
            <xs:element name="story"        type="xs:string"/>
        </xs:sequence>
    </xs:complexType>

    <xs:complexType name="yearType">
        <xs:simpleContent>
            <xs:extension base="xs:positiveInteger">
                <xs:attribute name="era"    type="xs:string"/>
            </xs:extension>
        </xs:simpleContent>
    </xs:complexType>
</xs:schema>

Answer 1

In your xml file, try with

xmlns:buildings="http://example/buildings/1.0/"

with a / final, as in your xsd declaration : xs:schema targetNamespace="http://example/buildings/1.0/"