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How can an SMTP Mailer application properly form an email so that Outlook resolves the FROM to internal user,etc?

I had this issue with some developers a while back, where their emails went to Outlook’s Junk E-mail folder. Even though it was from an internal email address, Outlook treated it as Internet email because it was just the email address.
So, I told them to try sending with the Mail from: and the FROM: Display Name….
That seemed to work.

Now we have some web app sending emails and it is doing the same – going to Outlook’s Junk E-mail folder.
I would rather try to find a solution on the mailer side, instead of trying to add it to safe senders on all PCs.

I’m trying to gather info so I can tell them exactly what should be happening.
From what I gather; to do this via command line, you do it like the below example. See any issues with that syntax?
(Note: Webapp@ourdomain.com is a valid distribution list address, we 3 dev dudes on it.)
helo ourdomain.com
mail from: webapp@ourdomain.com
rcpt to: Joe.user@@ourdomain.com
To: Joe User <joe.user@ourdomain.com>
From: Web App <webapp@ourdomain.com>
Subject: Please respond to our survey

Please take a moment to respond to our survey

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When it hits Outlook it just displays as shown:   Web App <webapp@ourdomain.com>
The properties just show the SMTP properties as if it was internet email.

Any suggestions?
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What version of exchange are you using?  Canyou provide a screen shot of what it looks like in Outlook.  Also how about the header information from an email?

Jian An LimSolutions Architect
Top Expert 2016

i have a bad feeling is the Outlook kicks in.

one thing you can do is to ask your telnet application to authenticate to the server, so the email was sent as an authenticated users rather then non-authenticated.

non-authenticated trigger a potential that it would be

X-MS-Exchange-Organization-SCL: -1 <--- exchange tell them it is safe and trusted

Outlook 2007 onwards usually observes this settings.

Paul MacDonaldDirector, Information Systems

As described, this isn't an SMTP mailer problem, but an Outlook problem.  

There's also no information on what language or tools are being used to generate the SMTP maiil.  I can say that in .Net, creating an SMTP mail object with a sender formatted like...
   objMail.From = New Net.Mail.MailAddress("PenSoft Weekly Free Software Drawing <Info@PenSoft.com>")
...is valid, and would seem to sidestep the problem you're experiencing.  This same format may or may not work with other SMTP mailers.
Tried authentication from the web app. Didn't matter.
Adding a "Friendly Name" helps... but doesn't fix it. i thoght it had fixed a previous web app, but it had just allowed the majority through. I guess Outlook just gives more legitimacy to an email with a name on it.

I figured this out though, on the Exchange (2003) side. Protocols > SMTP Properties per server.
Allow anonymous, and "resolve anonymous...".

The main drawback is if someone forged an email FROM joe.user@comany.com via SMTP if this is wide open. because it is resolved to the actual email object when Outlook gets it. So you click properties and it shows the AD/Exchange info. Without resolving you just see the SMTP friendly name and email address that was given in the SMTP session.

Anyway, once an email is resolved to a user, etc withing Exchange, Outlook rules are not applied...
Answered my own question.
This fixes Outlook filtering of emails created in-house via SMTP.