Help: LDAP Authentication

[Sukanya Belsare <SukanyaB@commerceroute.com>]

In my windows GUI, for getting the search results from an LDAP server,
along with the search filter the user enters the
LDAP server name,
LDAP port number,
user-name for authentication and
password.

The function ldap_simple_bind_s() requires that distinguished name be
supplied for the user-name.

How to get the user-name's distinguished name when all I know is just 
the above 4 parameters?

Can you reply to this ASAP?
Your help is much appreciated.

Thanks.