If you want to specify the schema location(s) then that attribute
schemaLocation needs to be in the namespace
http://www.w3.org/2001/XMLSchema-instance and needs to have URL pairs
namespaceURL schemaURL as its value e.g.
  <root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://example.com/2007/ns1
http://example.com/schema1.xsd"
        xmlns="http://example.com/2007/ns1">

If you happen to have your own attribute named schemaLocation then you
need to make sure your schema defines that for the DVDTimestamps element.

Thanks for your reply.

I am still getting the error.

The modified tag is now:

<DVDTimestamps xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://tenbase2.com/DVDTimestamps DVDTimestampXmlSchema.xsd"
        xmlns="http://tenbase2.com/DVDTimestamps">

I also used a url and full path for schema file name.

Regards,
William Johnston

Thanks again for your reply.

The init code for the validating XML reader is:

               StreamReader stream = new StreamReader(strFilename);

               // Create the XmlSchemaSet class.
               DVDXmlSchemaSet sc = new DVDXmlSchemaSet(strTargetNamespace, strSchemaFilename);

               XmlReaderSettings settings = new XmlReaderSettings();
               settings.ValidationType = ValidationType.Schema;
               settings.ValidationFlags |= XmlSchemaValidationFlags.None;
               settings.Schemas = sc;
               settings.ValidationEventHandler += new ValidationEventHandler(ValidationCallBack);
               
               reader = XmlReader.Create(stream, settings);

       /// <summary>
       /// schema filename
       /// </summary>
       private static string strTargetNamespace = "urn:DVDTimestamps";
       /// <summary>
       /// schema filename
       /// </summary>
       private static string strSchemaFilename = "DVDTimestampXmlSchema.xsd";

The DVDXmlSchemaSet class has a base class of XmlSchemaSet and has a constructor of:

   class DVDXmlSchemaSet : MyXmlSchemaSet
   {
       public DVDXmlSchemaSet(string strTargetNamespace, string strFileName)
           : base(strTargetNamespace, strSchemaPath, strFileName)
       {
       }
       /// <summary>
       /// field that contains the XML schema path
       /// </summary>
       public static string strSchemaPath = "G:\\DVD\\MyPrograms output\\xml schemas\\";
   }

Finally, the MyXmlSchemaSet constructor is:

       public MyXmlSchemaSet(string strTargetNamespace, string strPath, string strFilename) : base()
       {
           object[] formatParams = new object[2];
           formatParams[0] = strPath;
           formatParams[1] = strFilename;
           string strSchemaFile = string.Format("{0}{1}", formatParams);
           Add(strTargetNamespace, strSchemaFile);
       }

The exact exception and error message is:

System.Xml.Schema.XmlSchemaValidationException: "The 'http://tenbase2.com/DVDTimestamps:schemaLocation' attribute is not declared."

Regards,
William Johnston