Ldap issue

I tried to search using below commnad and I am getting following error

ldapsearch -x -H ldap:// -D "cn=manager,ou=system,o=example" -w secret

ldap_bind: Invalid credentials (49)

My slapd.conf contents is as below:
database bdb
suffix o=example.com
rootdn cn=manager,ou=system,o=example.com
# Cleartext passwords, especially for the rootdn, should
# be avoided. See slappasswd(8) and slapd.conf(5) for details.
# Use of strong authentication encouraged.
rootpw secret
#rootpw {SSHA}JvA5Ovk302pb39afL2yVk9VeAeMNCZAm
# rootpw {crypt}ijFYNcSNctBYg

#access to *
# by * write

access to dn.subtree="o=example.com"
by dn="cn=ldaproot,ou=system,o=example.com" write
by * auth
allow update_anon
access to * by anonymous read
# This allows the ldaproot to extract as much info as possible from the DB
limits dn.exact="cn=ldaproot,ou=system,o=example.com" size=unlimited time=unlimited

# The database directory MUST exist prior to running slapd AND
# should only be accessible by the slapd and slap tools.
# Mode 700 recommended.
directory /var/lib/ldap

# Indices to maintain for this database
index objectClass eq,pres
index ou,cn,mail,surname,givenname eq,pres,sub
index uidNumber,gidNumber,loginShell eq,pres
index uid,memberUid eq,pres,sub
index nisMapName,nisMapEntry eq,pres,sub

# logging setting
loglevel none

# Replicas of this database
#replogfile /var/lib/ldap/openldap-master-replog
#replica host=ldap-1.example.com:389 starttls=critical
# bindmethod=sasl saslmech=GSSAPI
# authcId=host/ldap-master.example.com@EXAMPLE.COM