Error inside a stored procedure is not being raised to my front-end applications using ADO. But I get the error when I run the procedure from Query Analyzer?

This typically happens when your stored procedure is returning multiple resultsets and the offending SQL statement is executed after returning one or more resultsets. ADO will not return an error untill it processes all the recordsets returned before the offending SQL statement got executed. So, to get to the error message returned by your procedure. You have to loop through all the recordsets returned. ADO Recordset object has a method called NextRecordset, which lets you loop through the recordsets.