Hi Geetika,
Both Administrator and geetika accounts must be in the OU=SPEC,OU=SPTEST,DC=xxxxx1,DC=com "container".
The sAMAccountName attribute is a single-valued attribute that is the logon name used to support clients and servers.
If this is a Microsoft's LDAP-based Active Directory, you can use the ADSI Edit to validate the value of sAMAccountName attribute for the Administrator account.
The Administrator account is in the CN=Users,DC=xxxx03,DC=com "container".
So I will fill in as follows:
Login Name Pattern: sAMAccountName={0}
Base User Directory: CN=Users,DC=xxxx03,DC=com
Connection Name: CN=Administrator,CN=Users,DC=xxxx03,DC=com
Connection Password: **********
Test user: Administrator
Test password: **********
Thanks,
Silvio