linkedserver SQL/ORACLE - An error occurred while preparing a query for execution -

my problem same... have code use in db utils class make query.

    public dataset sqlcommandselect(string command)     {         try         {             dataset objdataset = new dataset();             string strorders = command             sqlcommand objordercommand = new sqlcommand(strorders, myconnection);             sqldataadapter objordadapter = new sqldataadapter();             objordadapter.selectcommand = objordercommand;             objordadapter.fill(objdataset);             objordercommand.dispose();             objordadapter.dispose();             return objdataset;         }         catch (exception ex)         {             log.error("sqlcommandselect : " + command + " " + ex.message + " " + ex.stacktrace);             return null;         }     } 

now trying make query (that work greats on sql editor)

        select *          openquery(oracdgmi,'select * cic.anagrafica ') 

oracdgmi linkedserver sql/oracle

give me error:

        error occurred while preparing query execution  

any suggestion?