Alter table - adding constraints?

[Jay Paulson]

I really don¹t know what to do because I keep getting this error.  Any
ideas?

SQL query:

ALTER TABLE pl_reports ADD CONSTRAINT fk_region FOREIGN KEY ( region )
REFERENCES Region( id ) ON UPDATE CASCADE ON DELETE CASCADE

MySQL said: Documentation
#1005 - Can't create table './survey_localhost/#sql-113_f8.frm' (errno: 150)

Thanks!