Hi Hari,
ADManager Plus works with LDAP attributes and headers. Please ensure the CSV file which you're using has LDAP Headers (Headers are case sensitive). The LDAP header should contain suitable values. Please see sample CSV file given below,
givenName,sn,sAMAccountName,title,department
test,admp,t.admp,testing,Engineering
john,smith,jsmith,test,Electrical
The issue which you're facing might occur when there are no values specified for one of the LDAP headeres in teh CSV file.
ADManager Plus Team
Toll Free:+1888-720-9500 Email: ADManager Plus - Active Directory Management & Reporting Software