Hi Hari,

Problem in you r code is that since the lead object is throwing the error because of that your custom object is also not saved.

this is because both of these DML opertaions are happeing in single context and becuase of failure of the second one (your Lead) the first one (Custome object insert) is rollbacked.

So instead on insert use below one

Database.insert(dupLeadObj,false); // false means if any other operatin fails soes not roll back

Just tested in my org, this does not work. (This was my thought as well to resolve this....

Since the error is added to a different object during the same transaction the database.insert  gets rolled back as well.

hmm, Try to move the creation of of yur custom object in some helper class like below and future annotation over it

public class Utils{

@future

prublic static createMyCustomObj(Lead mylead){

 DuplicatLeadObject__c dupLeadObj = new DuplicatLeadObject__c();
                dupLeadObj.Duplicate_Lead_Info__c = mylead.Working_Planet_Category_c1__c+'<br>'+mylead.Working_Planet_Source_source__c+'<br>'+mylead.Working_Planet_Keyword_kw__c+'<br>'+mylead.Working_Planet_Ad_cr5__c+'<br>'+mylead.Working_Planet_User_IP__c+'<br>'+mylead.Working_Planet_Timestamp__c+'<br>'+mylead.Company+'<br>'+mylead.Email+'<br>'+mylead.FirstName+'<br>'+mylead.LastName+'<br>'+mylead.Phone+'<br>'+mylead.Title;
                dupLeadObj.Name = str;
                insert dupLeadObj;

}

}

You cannot pass objects to @future methods....