Thanks for he quick reply.
I followed thos guide:
>> Is it smtp auth or pop3/imap auth. Please clarify this
Exim dont have any user authentication and therefore most mailservers
reject mail from it because of the relay.
>> Are you able to send mails with out Auth from localhost ?
Yes I am able to.
>> Did you notice any error in exim logs ?
No there are no related error logs.
Could you rather please point me to a well working guide ?