title: Data Conversion Issue in SSIS package - Text to GUID
body: <p>I am developing a SSIS package that will open an Excel spreadsheet and import the data into a database table in SQL Server 2008.  When I try to convert the Excel column data type: <code>Unicode String [DT_WSTR]</code> to a unique identifier data type: <code>unique identifier [DT_GUID]</code>, I get the following error:</p>
  
  <p>"Invalid character value for cast specification"</p>
  
  <p>What do I need to do to resolve the conversion error?</p>