girando qui e la ho trovato questo:
codice:
using System;
namespace ConsoleApplication5
{
    class Class1
    {
        static void Main(string[] args)
        {
            try
            {
                JRO.JetEngine jro = new JRO.JetEngine();

                string OldDb = "Provider=Microsoft.Jet.OLEDB.4.0;" +
                    "Data Source=<Path_to_your_database>\\nwind.mdb";
                string NewDb = "Provider=Microsoft.Jet.OLEDB.4.0;" +
                    "Data Source=<Path_to_new_database>\\new_nwind.mdb";

                jro.CompactDatabase(OldDb,NewDb);
                Console.WriteLine("Finished Compacting Database");
            }
            catch(Exception e)
            {
                Console.Write("The following error occurred:" + e.Message);
            }
        }
    }
}