I am has a problem with sending e-mails.

I use a Trial Enterprise version.

A some weeks, the e-mails are sending normally.

Now, the e-mail send, but some recipients don't received.

Internal e-mails arrive normally.

If I logon in the mail server, the e-mail send normally.

In the support file, don't have errors.

Recent I change the Virtual Machine of Server 2012 for another Server 2012.

Example:
I open a ticket for user with e-mail xxx@live.com. And I receive all tickets open in my e-mail leandro@mybusiness.com

The server mail is @mybusiness.com

I receive the e-mail with the ticket, but the user don't.

Forwards and reply too don't arrived in mailbox of user.

I create a new instance of ManageEngine and works fine.

What is problem?