I have a connection string to read an excel file from my C# project that looks like this..
String ConnectionString = \"Provider=Microsoft.ACE.OLEDB.12.0;\"
There are different providers for connecting to Excel. Maybe you should try using a different one. Have a look at the examples here:
http://www.connectionstrings.com/excel
Providers for Excel » Microsoft Jet OLE DB 4.0 » ACE OLEDB 12.0 » .NET Framework Data Provider for OLE DB (OleDbConnection) » Microsoft Excel ODBC Driver » .NET Framework Data Provider for ODBC (OdbcConnection) » .NET xlReader for Microsoft Excel (ExcelConnection)
In your case you should have something like this: Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myOldExcelFile.xls;Extended Properties="Excel 12.0;HDR=YES";