in grid.recordsource i have

select io.status, io.empno, proper(alltrim(emp.lastname)+", "+alltrim(emp.firstname)+iif(!empty(emp.mid)," "+emp.mid+".","")), io.signdate, io.signout, io.signin, io.comments from inout io, employee emp where emp.empno=io.empno into cursor sys(2015)

form is running with no error. but when i try to modify the recordsource of my grid with this,

select io.status, io.empno, proper(alltrim(emp.lastname)+", "+alltrim(emp.firstname)+iif(!empty(emp.mid)," "+emp.mid+".","")), io.signdate, io.signout, io.signin, cm.comments from inout io, employee emp, comments cm where emp.empno=io.empno and cm.comid=io.comid into cursor sys(2015)
i changed the field comments in table inout to comid, then create another table comment with fields comid and comments.

when i run this SQL in the command window, i get the correct records in the cursor. but when i put this in the recordsource of grid, i get the error property value is invalid

what should i do? pls help. TIA.