NODBC

Navision Version 4.00 I have created an Excel spreadsheet that contains a pivot table with data connected using the Navision ODBC driver. All works well with the exception of using the refresh when Navision is open. Is this a flaw of the driver or do I need to set the connection up differently. This is set up as a System DSN; options are default except ‘Read Only’ is checked. Any Suggestions would be helpful