============ Required information ====
- iRedMail version: 0.8.7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Linux/BSD distribution name and version: Ubuntu 12.04
- Related log if you're reporting an issue:
====
When I installed iRedMail, I wasn't able to send mail from Outlook,and the mails sent from yahoo also was getting too much delayed.
So  disable greylisting. So receiving issue was solved that way. But when I send email to any external mail provider(Gmail, Yahoo, Outlook.com), my mail is is always marked spam or junk.

The results from  (http://www.mail-tester.com/) here was 10/10 and the DKIM key test using "amavisd-new testKeys" gave a pass
I tested SPF using (http://mxtoolbox.com/SuperTool.aspx) and that also was ok. Next thing I did was sending mail to (check-auth@verifier.port25.com'). The reply from it is given below

==========================================================
Summary of Results
==========================================================
SPF check:          pass
DomainKeys check:   neutral
DKIM check:         pass
Sender-ID check:    pass
SpamAssassin check: ham

I've attached some of Yahoo(It considers my mail as bulk) header below and you can find the gmail one from the attachment

Below is the yahoo mail header
X-Apparently-To: xyz@yahoo.com via 98.138.91.217; Mon, 04 Aug 2014 07:02:58 +0000
Return-Path: <xyz@domain.com>
X-YahooFilteredBulk: xxx.xxx.xxx.xxx

Is there anything I could do so that my mails doesn't get marked as SPAM??