Implementing Variable Envelope Return Path (VERP) using Exchange

email-bouncesexchange-2010

We're looking into implementing Variable Envelope Return Path (VERP) for improved bounce processing for our application.

Our current mail infrastructure is MS Exchange 2007 but are in the process of upgrading to 2010. We're also implementing Postini for spam filtering.

Exchange doesn't support sub-addressing (see also this question on disposable addresses) — and VERP is somewhat of a specialized application of sub-addressing.

Are there any options for implementing VERP in Exchange without putting another non-Exchange SMTP relay in front of Exchange to pre-process incoming messages? Specifically could a transport rule be created that could match against the target (non-existing) recipient, store that recipient address in a special header added to the message, and redirect the message to a pre-created mailbox?

Note: we have developer resources available if custom code could be used somehow.

Best Answer

Certainly, out of the box, there is no support for VERP in Exchange 2007/2010. As you know. I don't believe you'll be able to create a transport rule, even with PowerShell, to do what you want. I believe the closest you will get is building your own Transport Agent. You can find the Exchange SDK at msdn.microsoft.com. If your goal is to determine who a message bounced for, you may be better off parsing the protocol logs. Protocol logging must be turned on, and has separate send/receive logs. Good luck, Paul

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Single-Signon options for Exchange 2010

We decided that the combination of adding "ClearPass" to CAS and modifying the Exchange setup was going to be too hard to maintain, so our final solution is something like the squirrelmail solution that we didn't like.

That is, we send HTML like this to the user ($something generally means an already properly escaped variable) from a button they push in our in-house portal. This is the version where forefront is simply doing a straight pass-thru:

<html>
<body onLoad="javascript:document.forms[0].submit()">
<noscript>
 <h1>Redirecting you to $title</h1>
 <p>If you are not taken to $title within 15 seconds,<br />
    please click the button below:</p>
 </noscript>
 <form method="POST"
       action="https://$exchangehost/owa/auth/owaauth.dll" 
       name="logonForm" 
       enctype="application/x-www-form-urlencoded" autocomplete="off">
   <input type="hidden" name="destination" value="https://$exchangehost/OWA/" />
   <input type="hidden" name="flags" value="0" />
   <input type="hidden" name="forcedownlevel" value="0" />
   <input type="hidden" name="trusted" value="0" />
   <input type="hidden" name="username" value="$uid" />
   <input type="hidden" name="password" value="$password" />
   <input type="hidden" name="isUtf8" value="1" />
   <noscript>
     <input type="submit" value="$title" />
   </noscript>
 </form>
 </body>
 </html>

Mainly this is from copying the login form and making everything into hidden fields, but you need to change the URL on the action from /owa/auth.owa to /owa/auth/owaauth.dll.

We also tried having forefront do the authentication to OWA, here's the form for that (the <body onLoad=...> and the rest is basically the same):

<form method="post" action="https://$exchangehost/CookieAuth.dll?Logon">
  <input type="hidden" name="curl" value="Z2FowaZ2F" />
  <input type="hidden" name="flags" value="0" />
  <input type="forcedownlevel" value="0" />
  <input type="formdir" value="1" />
  <input type="rdoPblc" value="1" />
  <input type="username" value="$domain\$uid" />
  <input type="password" value="$password" />
</form>

Trying to set up a catch all e-mail in Exchange 2010

Per that article, having a Hub Transport do the job won't work:

Recipients are resolved before messages pass through the Transport Rules agent on Hub Transport servers. Therefore, transport rules on Hub Transport servers can't be used to copy or redirect messages to a catch-all mailbox.

Best Answer

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Single-Signon options for Exchange 2010

Trying to set up a catch all e-mail in Exchange 2010

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