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Exchange 2007 Content Filter Blocking An Email For One User

Posted on 2010-11-13
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Last Modified: 2012-05-10
We have a small domain network of five users using Small Business Server 2008 and our email is handled by Exchange 2007 using Outlook 2010. The problem we have is that Exchange server is blocking an email sent from a classic ASP CDO Script. It only affects one user on the network, if I change the recipient address to someone else in the GAL the mail gets through or if I send it to a separate POP3 account it works fine, I hope this means there is no problem with the script (The script is listed below). I think I have narrowed down the problem to the content filter because if I disable it the email will arrive in the effected users Inbox almost immediately, likewise if I whitelist the email address using “Set-ContentFilterConfig -BypassedSenders no_reply@clientone.com”  at the Exchange Management Shell the email will arrive almost immediately, This is not really a satisfactory solution as we will use this script for different clients and email addresses and the same user never receives the emails. The affected users main email address, joe@company.com is in the GAL however the script uses an alternative email address for the user of development@company.com which is set up in exchange

Our content filter settings are:
Delete massages with an SCL of 9
Reject messages with an SCL greater or equal to 7
Quarantine messages with an SCL greater or equal to 5
Quarantined messages are delivered to a redundant mailbox on exchange and one of the quarantined messages is shown below:-

Diagnostic information for administrators:
 Generating server: domain.lan
 development@company.com
#550 5.2.1 Content Filter agent quarantined this message ##
 Original message headers:
 Received: from cust-smtp-193.fasthosts.net.uk (213.171.216.60) by
 remote.company.com (192.168.30.35) with Microsoft SMTP Server id 8.1.436.0;
 Thu, 11 Nov 2010 10:42:28 +0000
Received: from IIS6105 (server213-171-218-105.livedns.org.uk
 [213.171.218.105])      by cust-smtp-193.fasthosts.net.uk (Postfix) with SMTP id
 9693E141004E    for <development@company.com>; Thu, 11 Nov 2010 10:42:27 +0000
 (GMT)
Thread-Topic: Client One Contact Us Form
X-Mailer: Microsoft CDO for Windows 2000
thread-index: AcuBjSDPBCwBJGQPRbuRSCVadxYPxA==
From: <no_reply@clientone.com>
To: <development@company.com>
Subject: Client One Contact Us Form
Date: Thu, 11 Nov 2010 10:42:25 +0000
Message-ID: <D7F10284126B47E8893FE9CAC72EFE0E@VHOSTS3.LOCAL>
MIME-Version: 1.0
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.3790.4721
Content-Class: urn:content-classes:message
Importance: normal
Priority: normal
Return-Path: no_no_reply@clientone.com
Received-SPF: None (SERVER.company.lan: no_reply@clientone.com does not
 designate permitted sender hosts)

The ASP CDO scripts are sent using a Fasthosts server and a sample is:-

Set myMail=CreateObject("CDO.Message")
myMail.Subject="Contact Us Form"
myMail.From=no_reply@clientone.com
myMail.To="development@company.com"
' the email
myMail.TextBody= "Date/Time: " & Date() & " - " & Time() & vbcrlf & vbcrlf
myMail.TextBody=myMail.TextBody & "Name: " & FRMname & vbcrlf & vbcrlf
myMail.TextBody=myMail.TextBody & "Telephone: " & FRMphone & vbcrlf & vbcrlf
myMail.TextBody=myMail.TextBody & "Email Address: " & FRMemail & vbcrlf & vbcrlf
myMail.TextBody=myMail.TextBody & "Subject: " & FRMsubject & vbcrlf & vbcrlf
myMail.TextBody=myMail.TextBody & "Message: " & FRMmessage & vbcrlf & vbcrlf
myMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/sendusing")=2
'Name or IP of remote SMTP server
myMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpserver")="smtp.fasthosts.co.uk"
'Server port
myMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpserverport")=25
myMail.Configuration.Fields.Update
myMail.Send
set myMail=nothing

Sorry for such a long post but I have tried to include all the relevant information, I look forward to hearing your comments and suggestions.

Thank you,

Dave

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Comment
Question by:Declaro
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6 Comments
 
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Accepted Solution

by:
Shack-Daddy earned 500 total points
ID: 34130114
What if we said that the core of the issue was that sending it to a secondary email address for the user (not the primary one found in the GAL) was the key variable? Would you say that based on your testing that is true?

If you found that the content filter would reliably block delivery to a mailbox if the primary email address was not used, then how about creating a workaround with an email-enabled distribution list instead of using an additional alias on a user mailbox?

Or how about sending it to a service mailbox (development@company.com) and the configure that mailbox to forward a copy (and not keep a local copy) to whichever user(s) is appropriate?
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Author Comment

by:Declaro
ID: 34130495
Hi Shack-Daddy,

Thanks for the response, Is was hoping it was caused by not being in the GAL, I am only a basic user of Exchange and do not really understand distribution lists properly but if that is the problem a service mailbox should work :) i have implemented that now for the user and I will test it tomorrow when he is back in the office and let you know.

Thanks for steering me in a new direction.
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Expert Comment

by:lala187
ID: 34134161
ok soz m8 dus the mail get blocked or quarantined?
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Author Comment

by:Declaro
ID: 34135359
Thanks for your input lala187, the mail would sometimes be rejected but mostly quarantined, I seem to have got it sorted now thanks to Shack-Daddy, I created a service email account and forwarded the emails to the affected user without storing a local copy and it appears to have worked, he is now getting the mail, hopefully it will work for other email addresses we will have to use in the future.

Thanks to everyone who contributed.

Dave
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Expert Comment

by:lala187
ID: 34135458
just remember you get a higher spam score wen you don't use a authenticated smtp. that is y you get the quarantine and rejected massages to some users. you can always add your subject words to the content filter so it will allow your mail to pass with no rule filter.  Tested for the mail
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Author Comment

by:Declaro
ID: 34135965
Thanks for that lala187 it's a good idea and your advice is welcome as i'm learning about exchange on the job as it were :) it's one thing learning from videos but real world solutions and advice are always better.

Dave
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