roundcube works but outlook does not

Hi,
I installed the server with apache2 following this https://www.howtoforge.com/perfect-...l-php-pureftpd-postfix-dovecot-and-ispconfig3
everything is working really great. however because i am running my server on comcast residential isp, i had to change the configuration in roundcube to use comcast relayhosts.
so now roundcube works great and i can send emails.
however when i go into outlook and i try to send emails it wont work unless i also put the smtp of comcast relay in there but i dont want to do that as its my laptop and when i travel and i am not on comcast internet connection those relay hosts options wont work.
is there a way to setup an email client that it will connect to the server and whatever is already set in the server configuration as a relay through comcast that should work without having to put those setting also in outlook? someone posted to try this

nano /etc/postfix/main.cf
relayhost = [smtp.comcast.net]:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options =

save and close main.cf file

nano /etc/postfix/sasl_passwd
smtp.comcast.net comcastuser:comcastpassword

save and close

chown root:root /etc/postfix/sasl_passwd
chmod 600 /etc/postfix/sasl_passwd
postmap /etc/postfix/sasl_passwd
postfix reload

so i tried this but it still doesnt work? what can i do?

 

i did that and i get the following error when sending in outlook:
Your message did not reach some or all of the intended recipients.
Subject: send test
Sent: 7/5/2015 1:15 PM

The following recipient(s) cannot be reached:
'[email protected]' on 7/5/2015 1:15 PM
Server error: '454 4.7.1 <[email protected]>: Relay access denied'

can it be that because port 25 is blocked i am getting this message? is there a way to change the outgoing port to another port number like 2626 instead of 25 that outlook should use to connect to my server? then my server will send the actual email over the relayhost and their port??

thank you
Ben

 

i also get this email came in saying bad header:

The message WAS NOT relayed to:

<[email protected]>:

554 5.6.0 bounce, id=05912-02 - bad header


This nondelivery report was generated by the program amavisd-new at host server1.wellspringsoflife.com. Our internal reference code for your message is 05912-02/ni_Qy1-b2xsW


INVALID HEADER


Missing required header field: "Date"


Return-Path: <[email protected]>

From: Microsoft Outlook <[email protected]>

Subject: Microsoft Outlook Test Message

when i click on the details attachment it says:

Reporting-MTA: dns; server1.wellspringsoflife.com
Received-From-MTA: dns; server1.wellspringsoflife.com ([127.0.0.1])
Arrival-Date: Sun, 5 Jul 2015 13:16:50 -0400 (EDT)

Original-Recipient: rfc822;[email protected]
Final-Recipient: rfc822;[email protected]
Action: failed
Status: 5.6.0
Diagnostic-Code: smtp; 554 5.6.0 Bounce, id=05912-02 - BAD HEADER
Last-Attempt-Date: Sun, 5 Jul 2015 13:16:50 -0400 (EDT)
Final-Log-ID: 05912-02/ni_Qy1-b2xsW

 

anyone has a way to fix this?

 

i fixed this by opening another port on my firewall and forwarding that port to port 25, so it bypasses the block on port 25