title: how to create xsd to validate excel file
body: <p>good morning,
  i am in a win application in c# language.
  i have to read a excel file (both xls and xlsx) and i would validate it with an xsd file but i wrong something because i get an error:
  data at the root level is invalid. Line 1, position 1 
  if i use the same xsd with corrispondent xml file this work correctly so shoul be a problem in my excel file or in a code to validate my excel file.
  i have use this code:</p>
  
  <pre><code>     XmlReaderSettings booksSettings = new XmlReaderSettings();
       booksSettings.Schemas.Add("http://www.w3.org/2001/XMLSchema",XMLImportUsers.xsd");
       booksSettings.ValidationType = ValidationType.Schema;
       XmlReader books = XmlReader.Create(@"D:\test.xml",booksSettings);
  
        while (books.Read()) { }
  </code></pre>
  
  <p>my xsd</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
   &lt;xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"&gt;
    &lt;xs:element name="UserSettings"&gt;
     &lt;xs:complexType&gt;
       &lt;xs:sequence&gt;
      &lt;xs:element name="ID_UTENTE" type="xs:decimal" minOccurs="1" maxOccurs="1"/&gt;
      &lt;xs:element name="ID_GRUPPO" type="xs:decimal" minOccurs="0" maxOccurs="1"/&gt;
  </code></pre>
  
  <p>etc etc</p>
  
  <p>Can you help me and post a code example to validate xls /xlsx fine from an xsd?
  thanks in advance</p>