>yes, it does run if I remove any other field from the nrh14000 table or any other table. I dont think i've exceed the caracter limit.

Try:

SELECT A.Numemp, A.Area, A.Cate, A.Sdo_dia, A.Sec, A.Subsec, ;
A.Dir, A.Empresa, A.Cta_gasto, A.Depto, A.Programa, A.Consec, ;
A.Tnoemp, A.Desup, B.Nomemp, B.Rfc, B.Alta_nom, B.Alta_gob, ;
B.Fec_baja, B.Cla_sin, B.Quin_dia, B.Num_quin, B.N_imss, B.Fonacot, ;
B.Curp, B.Tarchc, C.Col_emp, C.Telefono, C.Dir_emp ;

If it doesn't work, sent me the SELECT and the 3 tables (1 record for each is ennough), and I'll tell you what's wrong.