The reason for this exception is because an error with connection string you prepare.
modify your connection string preparation like this
OleDbConnectionStringBuilder sb = OleDbConnectionStringBuilder ();
sb.Add("Provider", "Microsoft.Jet.Oledb.4.0");
sb.Add("Jet OLEDB:Database Password", "*******");
sb.Add("Jet OLEDB:System Database",sfd.FileName);
bookConn = new OleDbConnection(sb.ConnectionString);
You can also refer
here[
^] to know more about connection string preparations. &
building-better-connectionstrings-with-connectionstringbuilder/[
^]