Error on updating/adding record

I upsized (using Upsize Wizard) ACCESS back end to MSSQL 2000. Front end is still ACCESS. I'm getting error when trying to add or updated a record entry from front end.
The error message reads: 'Error # 3027 was generated by DAO.Recordset Cannot update. Database or object is read only.'

Thanks for any help.you should be using ADO not DAO