Executereader requires an open and available connection

[Manesh Pawar]

Hello,
I m getting an error "System.Invalid OperationExcept ion - Executereader requires an open and available connection"
I have Open an Connection, but still it throughs an Error. But it occurs Sometimes..

Following is the code,

 

 if (con == null)
     con = new OleDbConnection("" + StrConnection);
 
 if (con.State == ConnectionState.Closed)
     con.Open();
   OleDbCommand cmd = new OleDbCommand("Select (Max(BOMId)+1) as BOMNo from BOM ", con);
  [B][B][I]OleDbDataReader dr = cmd.ExecuteReader();[/I][/B] [/B][B][I]// error occurs at this Line  [/I][/B]
     while (dr.Read())
       {
          ----

What Could be the problem??