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We have emails sent to people within our company that are filtered into Outlook's Junk Mail. Basically, there is a signup form on our company's .Net website, and when people signup, these automated messages are sent.

This is confusing, because everything happens within our Windows domain. I do not know why Outlook would block mail within our own domain.

Even stranger, this behavior changes based in the "From" address. I can fix the problem by using the From address "" but the mail gets blocked when I try other From addresses. The From Addresses I tried and failed are: "", "", or "".

The text within the email seems very benign, in that I see nothing that a Spam content filter would want to block. If I could just use "" as our from address everything would be fine. But I can't use that address, so emails continue to get blocked for no apparent reason.

share|improve this question
Taking a step back, there's a reason this is going on based on what you're stating. Have a few questions: (1) Why's the company sending emails to itself within it's own network to test what appear to be email addresses for inbound external users. (2) There any differnces in how the emails are used, for example the sales@ email is the email used to route form submissions on the website, but the support@ email requires a mail client to contact. – blunders Jan 7 '12 at 3:35
(3) If you don't know how Microsoft's product works, and they won't tell you, why're you againts checking to see if any of the company's email assets have been blacklisted; e.g. emails, IPs, domains, etc.? (4) Have you viewed the full-emails with the headers included, since it's possible there's meta-data you're not seeing? – blunders Jan 7 '12 at 3:37
Sorry, I didn't mean to seem as though I were opposed to checking if we are blacklisted, besides the fact that everyone except us gets our emails, the issue is I do not know how, nor how to spot metadata in the headers that would cause this. Regarding your first question, we need this when users fill out a form on our webpage, and the email is a way to relay the information to the users in the company. Regarding question 2, I've tried using both Groups and actual email addresses in the From address and none have worked. Thanks. – David Jan 11 '12 at 21:58
Hmm, okay - putting all the above assigned for now, my suggestion would be to have each form email that's relayed have it's own internal address. For email "" - is that possible to do? Reason being that then you'd be 100% sure if it's the emails content that's being flagged; which based on the behavior you describe, should fix the issue. Another option would be to find a way to whitelist all emails from your domain with your internal IP range. – blunders Jan 11 '12 at 22:47
Thanks, What solved the issue was putting the sender's email address ( into Outlook contacts for each recipient. This is more of a workaround that an actual solution. I really appreciate your help. – David Jan 17 '12 at 19:19

The rules for what ends up in the junk folder in outlook are a bit of a mystery. There are some general guidelines people have produced... but Microsoft won't confirm/deny any of the logic... (or someone will use that as a guide to make spam designed to bypass the rules)

That being said... it's probably a good idea to make sure your web-server's IP didn't end up on one of the many spam-filter blacklists... as you may have accidentally set it up as a mail-relay... or some such.

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Awesome, so Microsoft doesn't have a way to whitelist emails, domains, IPs, etc.? – blunders Jan 6 '12 at 19:11
You can ... but as far as I know there is no easy way to apply this domain-wide: – TheCompWiz Jan 6 '12 at 19:16
CompWiz, this is all (sending and receiving) internal to our network, so I'm not sure if blacklists are the issue. The email is sent successfully to emails outside our domain. It seems Outlook or Exchange is the culprit, and there is no way to mark the message as safe. – David Jan 6 '12 at 19:49
up vote 1 down vote accepted

What solved the issue was putting the sender's email address ( into Outlook Contacts for each recipient. This is more of a workaround that an actual solution.

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