Hi Raj,
the config that you have shown in the screenshots looks correct. My guess is that the LDAP connection is not pointing to the correct "structure" in the AD.
Can you use transaction LDAP and and browse through the connection? Are you seeing the user objects that you are expecting?
I fear the next step would be to debug... You might also want to create an OSS / CSN ticket so that we can connect to your system and support you in the configuration.
Regards,
Holger.