SQL Server 2014 Not recognizing 64 bit drivers for Office
When attempting to reproduce your issue, I received the following error: 


  the 'microsoft.ace.oledb.12.0' provider is not registered on the local
  machine


I downloaded the 2007 Office System Driver:  Data Connectivity Components
to resolve the error.  When I choose to export data to Excel and choose a file name of .xls, the export will error at 65,536 rows.  If I choose to export data to Excel and select a file name of .xlsx, the export will complete without error.  This is because in Excel 2010 there is a 1048576 row limit per sheet, and in Excel 97 there is a 65536 row limit per sheet.