PIX 501 (Sending mail to some ISP's Does not work)

Hello All;

  I was just reading this post:
http:Q_21783452.html#16301133

I have this in my Configuration:

global (outside) 1 interface
global (outside) 1 xx.xxx.xxx.87  <-- This is assigned to the PIX
nat (inside) 1 0.0.0.0.0.0.0.0 0

============
In the provided link above, I see where [brainbolt] had done this:
============
global (outside) 10 x.x.x.123  
nat (inside) 10 10.0.1.11 255.255.255.255 0 0
============
of which the    10.0.1.11     <-- Goes to his Exchange Mail Server.
============

Our Mailserver is:       192.168.1.182   & 192.168.1.181
(Of which both point to their own External IP Address's)

How can I setup these "2" IP Address's within PIX Configuration so that "Hopefully" We can
Send/Receive Mail from such ISP's as AOL?

Thanks all
Carrzkiss
LVL 31
Wayne BarronAuthor, Web DeveloperAsked:
Who is Participating?
 
Cyclops3590Connect With a Mentor Commented:
Right, exactly.  Even though you host your DNS zone, it is only the forward zone.  Whoever hosts the reverse zone containing your IP needs to take care of that PTR entry.  Once that is done, then the AOL mailing is half ok.  Unfortunately you have to wait until you get rate limited and then apply to be whitelisted.  In AOL's infinite wisdom, you can't apply for whitelisting an IP in their database until after you have a history with them (briliant, eh?)
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Cyclops3590Commented:
just putting in static lines in your pix config isn't enough for ISPs like AOL
first, pix config
static (inside,outside) <public ip> 192.168.1.182 netmask 255.255.255.255
static (inside,outside) <public ip> 192.168.1.181 netmask 255.255.255.255
also make sure to add the appropriate rules to your outside interface's acl for smtp traffic
BTW, static entries are processed before nat entries and are the preferred way of doing what you desire here.

as for AOL issues
you need to have a forward zone entry, reverse entry zone, and apply for whitelisting.
Forward zone entry will be an A and MX record placed in the zone hosted by whoever controls your forward zone
Reverse zone entry will be a PTR record for each server placed in the zone hosted by your ISP
After that is done, AOL will start accepting your traffic; however they will still rate-limit you
After you have sent them some traffic your IP will be in their records and you can finally apply for a whitelist entry at this URL
http://postmaster.aol.com/
look down in the list and you'll see a link pertaining to whitelisting
fill out that form and submit it.  It'll take about a week for them to process it.  Then you should be good.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Hello Cyclops;

   I already have these 2 entries in the PIX Config.

Our ISP has a Reverse Lookup Record for "All" of our Static IP's
And we are also hosting Reverse Lookup, Forward & PTR's for All Domains.
-------
I will contact AOL about the Whitelist issue and see what becomes of it.

Thanks
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Cyclops3590Commented:
if everything is configured right, then you should still be able to send to most anyone out there.  There really aren't that many people that enforce SPF filtering.

Can I see your pix config (sanitized of course)?  I'm curious if something else could be conflicting with what you are trying to do.

Also, did you run
clear xlate
after you added the static entries.  That needs to be ran or the translations get all screwed up.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Yes, clear xlate was run. The config have been like this for over 2yrs now.
==============
PIX Version 6.3(3)
interface ethernet0 auto
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password 8Ry2YjIyt7RRXU24 encrypted
passwd 2KFQnbNIdI.2KYOU encrypted
hostname pixfirewall
domain-name ciscopix.com
fixup protocol dns maximum-length 512
fixup protocol ftp 21
fixup protocol h323 h225 1720
fixup protocol h323 ras 1718-1719
fixup protocol http 80
fixup protocol rsh 514
fixup protocol rtsp 554
fixup protocol sip 5060
fixup protocol sip udp 5060
fixup protocol skinny 2000
fixup protocol smtp 25
fixup protocol sqlnet 1521
fixup protocol tftp 69
names
name 192.168.1.189 MasterPC
object-group service web tcp
  description web traffic
  port-object eq www
  port-object eq https
access-list outside_in permit tcp any host xx.xxx.xxx.76 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.77 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.78 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.79 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.80 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.82 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.83 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.84 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.76 eq ftp
access-list outside_in permit tcp any host xx.xxx.xxx.82 eq smtp
access-list outside_in permit tcp host 204.74.100.10 host xx.xxx.xxx.76 eq domai
n
access-list outside_in permit tcp host 204.74.97.97 host xx.xxx.xxx.76 eq domain

access-list outside_in permit tcp host 204.74.104.97 host xx.xxx.xxx.76 eq domai
n
access-list outside_in permit tcp any host xx.xxx.xxx.82 eq 8181
access-list outside_in permit tcp any host xx.xxx.xxx.82 eq pop3
access-list outside_in permit udp any host xx.xxx.xxx.76 eq nameserver
access-list outside_in permit tcp any host xx.xxx.xxx.76 eq domain
access-list outside_in permit udp any host xx.xxx.xxx.76 eq domain
access-list outside_in permit tcp any host xx.xxx.xxx.81 object-group web
access-list outside_in permit tcp any host xx.xxx.xxx.81 eq smtp
access-list outside_in permit tcp any host xx.xxx.xxx.81 eq 8181
access-list outside_in permit tcp any host xx.xxx.xxx.81 eq domain
access-list outside_in permit udp any host xx.xxx.xxx.81 eq domain
access-list outside_in permit tcp any host xx.xxx.xxx.81 eq pop3
access-list outside_in remark Windows Media Services
access-list outside_in permit tcp any host xx.xxx.xxx.84 eq 1755
access-list outside_in remark Windows Media Services
access-list outside_in permit udp any host xx.xxx.xxx.84 eq 1755
access-list outside_in permit tcp any host xx.xxx.xxx.90
access-list outside_in permit udp any host xx.xxx.xxx.90
pager lines 24
mtu outside 1500
mtu inside 1500
ip address outside dhcp setroute
ip address inside 192.168.1.1 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm location 192.168.1.176 255.255.255.255 inside
pdm location 192.168.1.177 255.255.255.255 inside
pdm location 192.168.1.178 255.255.255.255 inside
pdm location 192.168.1.179 255.255.255.255 inside
pdm location 192.168.1.180 255.255.255.255 inside
pdm location 192.168.1.182 255.255.255.255 inside
pdm location 192.168.1.183 255.255.255.255 inside
pdm location 192.168.1.184 255.255.255.255 inside
pdm location 192.168.1.185 255.255.255.255 inside
pdm location 192.168.1.186 255.255.255.255 inside
pdm location 192.168.1.187 255.255.255.255 inside
pdm location 204.74.97.97 255.255.255.255 outside
pdm location 204.74.100.10 255.255.255.255 outside
pdm location 204.74.104.97 255.255.255.255 outside
pdm location 192.168.1.191 255.255.255.255 inside
pdm location 192.168.0.1 255.255.255.255 inside
pdm location 192.168.1.181 255.255.255.255 inside
pdm location MasterPC 255.255.255.255 inside
pdm location 192.168.1.190 255.255.255.255 inside
pdm logging informational 100
pdm history enable
arp timeout 14400
global (outside) 1 interface
global (outside) 1 xx.xxx.xxx.87
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
static (inside,outside) xx.xxx.xxx.76 192.168.1.176 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.77 192.168.1.177 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.78 192.168.1.178 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.79 192.168.1.179 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.80 192.168.1.180 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.82 192.168.1.182 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.83 192.168.1.183 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.84 192.168.1.184 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.85 192.168.1.185 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.86 192.168.1.186 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.87 192.168.1.187 netmask 255.255.255.255 0 0

static (inside,outside) xx.xxx.xxx.81 192.168.1.181 netmask 255.255.255.255 0 0

static (inside,outside) MasterPC MasterPC netmask 255.255.255.255 0 0
static (inside,outside) xx.xxx.xxx.90 192.168.1.190 netmask 255.255.255.255 0 0

access-group outside_in in interface outside
timeout xlate 0:05:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225 1:00:00
timeout h323 0:05:00 mgcp 0:05:00 sip 0:30:00 sip_media 0:02:00
timeout uauth 0:05:00 absolute
aaa-server TACACS+ protocol tacacs+
aaa-server RADIUS protocol radius
aaa-server LOCAL protocol local
http server enable
http 192.168.1.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
telnet timeout 5
ssh timeout 5
console timeout 0
dhcpd address 192.168.1.2-192.168.1.129 inside
dhcpd dns 192.168.1.176 192.168.1.178
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
dhcpd enable inside
terminal width 80
Cryptochecksum:9dbef6f9169b8fc7e639315333ed3cac
: end
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I did the Reverse DNS test on the AOL Site, and it completed "Successfully"
So there is not a problem with that.
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Cyclops3590Commented:
why is this in there, don't you have static IPs (I'm assuming due to the number of statics)
ip address outside dhcp setroute

but I'm a little confused now.  you say that has been the config for the last couple of years.  but you say you can't send/receive email.  When did this start happening.  run a couple tests for me please.
from internal mail server
telnet gsmtp163.google.com 25

you should be presented with a banner.  if it times out, then there could be a firewall issue

from a machine on the internal network
telnet 192.168.1.181 25
telnet 192.168.1.182 25

you should see a banner on both.  now do the same on a machine outside the network (probably your home machine) but of course replace the internal IP with the public one.  do you see the banner?

I just need more information about what is not working, when it started, etc.
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Cyclops3590Commented:
btw, I read that link you posted.  although that guy had the correct translation coming in, he didn't for going out which was his problem.  Since you are using static NATs instead of PATs like he was, your problem isn't the same as his.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Sending e-mail to "some" ISP's does not work.
As in: AOL

I can send mail to: Hotmail, yahoo, googlemail, and nearly 99.9% of the rest, but not such sites as AOL.
So, the [Subject] (Sending mail to some ISP's Does not work)
Is accurate in this issue.

What are you referring to here:
[Quote]
why is this in there, don't you have static IPs
[/Quote]

Yes, all Telnet's Work properly like they have for the last couple of years.
----
And as for when it started, Not being Able to send to AOL.
That started when they changed their MailServer configurations (again).

-----
So what is the deal with the Config File?
Does everthing look OK? It should.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
OK. You was referring to:
ip address outside dhcp setroute

Some of the system's inhouse do run on Dynamic IP's
And when someone comes over with their Laptop, and connects to one of the 8-different locations
Where there is Ethernet Access, I do not want to have to get them to Assign an Internal IP Address.
(Make since?)
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Cyclops3590Commented:
right, thats fine, but that is why this part of the config is there
dhcpd address 192.168.1.2-192.168.1.129 inside
dhcpd dns 192.168.1.176 192.168.1.178
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
dhcpd enable inside

ip address outside dhcp setroute tries to assign an IP to the outside interface via dhcp.  that should be redone with the correct outside interface ip, then you can get rid of the global entry with the ip in it; basically do this
ip address outside <ip address> <mask>
no global (outside) 1 xx.xxx.xxx.87

I highly doubt its a pix issue then.  If you can send/receive email than the pix is ok.  I would have to say its either a SPF problem which you say is fine or a rate-limiting issue.  When the email gets rejected is there a reason error anywhere in the message?
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Cyclops3590Commented:
oh and clear xlate

and only do that during down time, since if there is a side-effect (which there shouldn't be), then you can always reload the pix and it'll be fine again (provided you saved the changes you actually truely wanted to keep since the last restart)
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
This is what I am showing in my Logs for the AOL Issue.


20060625 230753 127.0.0.1       SMTP (00B500C9) Trying aol.com (0)
20060625 230818 127.0.0.1       SMTPD (01450104) [192.168.1.182] connect 192.168.1.182 port 1829
20060625 230838 127.0.0.1       SMTP (00B500C9) MX connect fail "64.12.138.185"
20060625 230920 127.0.0.1       SMTPD (01470104) [192.168.1.182] connect 192.168.1.182 port 1836
20060625 230923 127.0.0.1       SMTP (00B500C9) MX connect fail "64.12.138.57"
20060625 231008 127.0.0.1       SMTP (00B500C9) MX connect fail "205.188.159.217"
20060625 231022 127.0.0.1       SMTPD (01490104) [192.168.1.182] connect 192.168.1.182 port 1844
20060625 231053 127.0.0.1       SMTP (00B500C9) MX connect fail "205.188.158.121"


It is connect 192.168.1.182
Which is the Internal IP Address, and not the External IP Address.
I have read that this could be the cause of not being able to send to AOL
Is that it is grabbing the Internal IP Address when trying to connect to AOL.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I just did a Whitelist Request with AOL, So will wait and see on what becomes on that?
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Cyclops3590Commented:
and if you can post a rejection error from one of the emails in the mean time it might be of some help too
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I am waiting on one to come back to me now.
In the meantime.
I receive the [Rejection] email from AOL - Whitelist Request.

===============================
Your web request has been denied due to insufficient mailer history. We
apologize for this inconvenience.  Please resubmit your request and also
include your IP addresses that have sent mail to AOL in the last 30 days.
Place these IP addresses in the section named "Additional Information."
===============================

Kind of hard to have a 30-Day History with AOL when I cannot send e-mail to the company.

In my honest opinion;
If everyone would stop using AOL then Mail Admin's would not have to put up with the crap of trying to setup their Configuration to work with AOL
Everytime that AOL decides that they want to go and "Change" their
Mail Server Config's due to something that they really have no control over.

That is just my opinion.

--------
I will post the Rejected e-mail once it comes back from my server.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
By the way.
I can receive e-mail from AOL.
But just cannot send to them?
As the rejection e-mail was sent to my Mail Server.
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Cyclops3590Commented:
My sentiments exactly with AOL.  I got the same message after I switched ISP who gave me new IP addresses.  and I believe I cursed the same exact thing.

By the way, from the mail server go to www.dnsstuff.com
In the upper right you'll see your IP address that it is seeing.  That is the correct IP, right?
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Yep, it shows the External IP Address
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
About time, took long enough.
If you see, the IP Address is the IP Address from my Laptop: carrzdeveloper 192.168.1.190
=========================================================================
Delivery failed 20 attempts: postmaster@aol.com


Original message follows.

Received: from carrzdeveloper [192.168.1.190] by carrz-fox-fire.com with ESMTP
  (SMTPD32-8.05) id A2A23200AA; Mon, 26 Jun 2006 13:00:18 -0400
Message-ID: <001d01c69942$d7403b40$be01a8c0@carrzdeveloper>
From: =?iso-8859-1?Q?xxx?= <xx@xxx.com>
To: "AOL Postmaster" <postmaster@aol.com>
References: <200606261651.k5QGpv611679@vext-s11.websys.aol.com>
Subject: Re: Request Confirmation
Date: Mon, 26 Jun 2006 13:06:18 -0400
MIME-Version: 1.0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2800.1807
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1807
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Cyclops3590Commented:
what type of mail server do you have.  There's no error code in the return message.  Whether you see it in queue or elsewhere, there should be a error code why delivery failed.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I need to start reading what I write, to make sure that I am adding everything in.

This is from Our Mail Logs.  Running:  IMail Server v8.x

20060626 171813 127.0.0.1       SMTP (00DE0010) Trying aol.com (0)
20060626 171846 127.0.0.1       SMTPD (01FD0150) [192.168.1.182] connect 192.168.1.182 port 1362
20060626 171858 127.0.0.1       SMTP (00DE0010) MX connect fail "205.188.157.25"
20060626 171943 127.0.0.1       SMTP (00DE0010) MX connect fail "205.188.159.57"
20060626 171948 127.0.0.1       SMTPD (01FF0150) [192.168.1.182] connect 192.168.1.182 port 1370
20060626 172028 127.0.0.1       SMTP (00DE0010) MX connect fail "205.188.156.249"
20060626 172050 127.0.0.1       SMTPD (02010150) [192.168.1.182] connect 192.168.1.182 port 1377
20060626 172113 127.0.0.1       SMTP (00DE0010) MX connect fail "205.188.158.121"
20060626 172113 127.0.0.1       SMTP (00DE0010) Creating message from Postmaster
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I posted the information that was needed.
Any suggestions on how to resolve this issue?

Thank you
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Cyclops3590Commented:
sorry about that.
just check at dnsstuff.com on your mail IP to see if its apart of any blacklists.  according to your logs, it can't even connect to the aol mail servers

also from your mail server do this
telnet 205.188.157.25 25

what do you get
also, try to ping that IP
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
From dnsstuff.com

These are the only area's

STARLOOP  DNS lookup error: SERVER FAILURE  
SPAMTHWART  DNS lookup error: SERVER FAILURE  
And this one as well:

FIVETENSRC
[should not be used]  LISTED (127.0.0.2)  Reports CNAME of 68.119.211.232.charter.com.misc.spam.blackholes.five-ten-sg.com.
TXT= "miscellaneous address blocks that have sent spam here"

(Which that is not my IP Address, but according to them, my IP is a CNAME from our ISP.
Of which we are trying to get them to drop everything on their end, so that we can do all of
OUr own DNS Hosting.

-------------
The [Telnet] timed out.
And [Ping] I cannot do behind the PIX.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Still waiting on something??? Anything really???
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Cyclops3590Commented:
Was on vacation for the 4th thru the weekend.

in order for ping to work you must allow atleast echo-reply on the outside interface.
as for telnet, can you do that command on any other command (one that should be translated to the main outside int IP address or any other computer that translates to other IPs.  Also, try the same telnet at your home box.

also, do the following
nslookup
>set type=mx
><your domain>                 <--to make sure the correct mx records are being projected to the world
>set type=a
><do for each mx record>
>set type=ptr
><do for each IP reported for each mx record>

Want to make sure you have the DNS right.  The MX check should give atleast one entry to a fqdn, the A check should give an IP for that fqdn, and the PTR check should give the same fqdn for the corresponding IP that was given during the A check
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
All records in DNS are set properly.
http://www.dnsreport.com/tools/dnsreport.ch?domain=carrz-fox-fire.com
(Ignore the [Open DNS Server] I am getting ready to setup and Inhouse DNS Server, and close
The External DNS Server so it will not be open. As soon as I can get the proper information fro
WinNT4 Windows DNS Server)

I will hook up to an External connection here in a few and run the test.
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Cyclops3590Commented:
PASS      
Reverse DNS entries for MX records      
OK. The IPs of all of your mail server(s) have reverse DNS (PTR) entries. RFC1912 2.1 says you should have a reverse DNS for all your mail servers. It is strongly urged that you have them, as many mailservers will not accept mail from mailservers with no reverse DNS entry. Note that this information is cached, so if you changed it recently, it will not be reflected here (see the www.DNSstuff.com Reverse DNS Tool for the current data). The reverse DNS entries are:

82.178.119.68.in-addr.arpa 68-119-178-082.static.snfr.nc.charter.com. [TTL=3199]

That is the one I'm talking about.  Contact your ISP to make sure your entry looks like this


68 (dot) 119 (dot) 178 (dot) 82  PTR  mail (dot) carrz-fox-fire (dot) com (dot)
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Cyclops3590Commented:
plus, not sure if it might be causing a problem or not, but it looks like you have a pix with the smtp fixup turned on.  This will usually break communication for mail servers that don't follow the smtp protocol (read: Microsoft)  However, this will also break esmtp protocol sessions as well.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
What would be the code for the :  fixup to turn on?
(Been a long time since I have messed around with connecting with "HyperTerminal".
Also, does the Web Interface have the "fixup" properties so that I can edit it there?
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Cyclops3590Commented:
umm, web int might, but I never use it

command line will be
no fixup protocol smtp 25

write mem
to save the config changes

however, if its been working this long with the fixup turned on, then I wouldn't mess with it.  Just keep in mind that it is turned on.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
I had spoke to our Business Rep the other week about this:
82.178.119.68.in-addr.arpa 68-119-178-082.static.snfr.nc.charter.com. [TTL=3199]

I told him that I would prefer to have it with Our company information on it.
Since we are leasing the 13-Static's from the ISP, he told me that it should not be a problem.
I told him that we host our own DNS here, that this is the only thing that is being done on their side,
And it could be causing some problems with the way certain ISP's may look at it.
Mainly, AOL.
As much as I hate AOL, there is still Millions of people that use it's service.
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Yep, a pain in the butt really.
OK, I will see if I can get the ISP off there butts and get this issue taken care off.
I will keep you post with my findings.

Cheers
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Wayne BarronAuthor, Web DeveloperAuthor Commented:
Cyclops3590
I needed to close this question, and since your last reply is best of all replies.
I awarded it the points.
I will still keep you posted on my Findings once everything is done.

I am going to contact my ISP Tech Support sometime tomorrow.
And see about have them either do the Reverse PTR on their end, (or)
Allowing me to do everything in Office (Inhouse) like I would prefer to do.

Thanks again for the needed information.

Wayne
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Cyclops3590Commented:
No problem, but I am 99% positive that is the issue of why your mail is getting rejected.
0
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