while importing access file it give format except in c#

Question

i'm importing access (office 2010)file using c# this my code

string excelConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\medi.xlsx;Extended Properties=""Excel 12.0 Xml;HDR=YES""";

// string excelConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\\medi.xlsx;Extended Properties=Excel 12.0;";

string sqlConnectionString =ConfigurationManager.ConnectionStrings["sqlcon"].ConnectionString;

//Create Connection to Excel work book

OleDbConnection excelConnection = new OleDbConnection(excelConnectionString);

//Create OleDbCommand to fetch data from Excel

OleDbCommand cmd = new OleDbCommand

("Select * from [medi1$]",excelConnection);

excelConnection.Open();

OleDbDataReader dReader;

dReader = cmd.ExecuteReader();

// Create object for SqlBulkCopy

SqlBulkCopy sqlBulk = new SqlBulkCopy(sqlConnectionString);

sqlBulk.DestinationTableName = "demo";

 sqlBulk.WriteToServer(dReader);