Naming violation (64) additional info: naming attribute 'co' is not present in LDAP entry

Question

Hi, i am new here, and i am looking for some help. The LDAP installation goes ok, but i have some promblems trying to add the attribute 'co' in LDAP entry. Here is my sldap.conf
SLAPD.CONF

# BDB Backend configuration file
# See slapd.conf(5) for details on configuration options.
# This file should NOT be world readable.
ucdata-path  ./ucdata
include    ./schema/core.schema
include    ./schema/cosine.schema
include    ./schema/nis.schema
include    ./schema/inetorgperson.schema
include    ./schema/my.schema
include    ./schema/openldap.schema
include    ./schema/dyngroup.schema


pidfile    ./run/slapd.pid
argsfile  ./run/slapd.args


# Enable TLS if port is defined for ldaps


TLSVerifyClient never
TLSCipherSuite HIGH:MEDIUM:-SSLv2
TLSCertificateFile ./secure/certs/server.pem
TLSCertificateKeyFile ./secure/certs/server.pem
TLSCACertificateFile ./secure/certs/server.pem


#######################################################################
# bdb database definitions
#######################################################################
database  monitor

database  bdb
suffix    "dc=ctpaldap01,dc=ctpa,dc=org,dc=uk"
rootdn    "cn=admin,dc=ctpaldap01,dc=ctpa,dc=org,dc=uk"
# Cleartext passwords, especially for the rootdn, should
# be avoid.  See slappasswd(8) and slapd.conf(5) for details.
# Use of strong authentication encouraged.
#rootpw  {SSHA}wWdai/i8QKux4wve+ZSVtqzoErZwjW44
rootpw !win3dow5

# The database directory MUST exist prior to running slapd AND
# should only be accessible by the slapd and slap tools.
# Mode 700 recommended.
directory ./data
dirtyread
searchstack 20
# Indices to maintain
index mail pres,eq
index objectclass pres
index default eq,sub
index sn eq,sub,subinitial
index telephonenumber
index cn