When a user sends an email on a non-mail service web site, the mail host on the receiver side often treats the email as a junk email since it is not sent from the mail host whoever the user's email account belong to. I have some complaints of this issue. The email functionalty is built with JavaMail.
Can it be resolved?
Easily. Change your system to send your mail from the server host where the from address belongs.
Ask yourself this: if you were an e-mail server and you got a mail that claimed to be from "bill.gates@microsoft.com", but it was sent from a server that didn't belong to Microsoft, what should you do?
> Easily. Change your system to send your mail from the
> server host where the from address belongs.
"Easily"? How does this will happen? "Change your system to send your mail from the server host where the from address belongs."
And, the e-mailing is a private communication method between the users who have their email accounts of various email hosts. The system needs to switch the mail host each time when a user uses a different email host if the above can be done?
I can't make any sense out of those sentences. Here's what you should do. For example if you're sending e-mail messages that claim to come from "vwu@vancouver.ca" then you should connect to an SMTP server that is in the vancouver.ca domain and ask it to send those messages. This is easy for most people. Why is it difficult for you?
It certainly is not easy for me. Any visitors can forward the web site content to another by entering his/her email address. I can抰 see how it is easy to collect all outgoing servers (SMTP) for any possible email addresses. It is easy to find SMTPs of free web email hostings such as Hotmail, Yahoo, etc. I don抰 know/believe that an outgoing email server name of a private company is publicly accessible.
You basically have three choices.
1. Ask the user what mail server they use, including all the information
necessary to authenticate to that mail server.
2. Run your own mail server, configured to allow anyone on your web
site to send email with any From address, and accept the responsibility
to secure your mail server against use by spammers. Still, since the
From address will essentially be forged by your mail server, some other
mail servers might reject such messages.
3. Contract #2 to someone experienced in running mail servers.
