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I am trying to use the console in Fedora 17 to send an automated email to myself.

I run this:

echo "email content" | mail -s "blah"

It works fine, google treats it as a spam email, but when you mark it not spam everything is cool. For Hotmail there are policies to prevent the email from being sent.

I do this:

echo "email content" | mail -s "blah"

And the email returns as undeliverable, the email does not even appear in the spam folder and I get this as a response:

----- Transcript of session follows -----
... while talking to
>>> MAIL From:<> SIZE=685
<<< 550 DY-001 (BAY0-MC3-F8) Unfortunately, messages from 
weren't sent. Please contact your
+Internet service provider. You can tell them that Hotmail does not relay 
dynamically-assigned IP ranges.
+You can also refer your provider to
554 5.0.0 Service unavailable

So apparently hotmail doesn't like spammers so much, they they are blocking anything with a dynamically assigned IP range. Google does not do this. What is the easiest way to just get around this and send an email to hotmail and end up in their spam folder to be unblocked later by the user?

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up vote 1 down vote accepted

There's no way, while using a dynamic IP range, to ensure that a mail server accepts your email.

You could try to make your email appear less spammy, in hopes that the receiving mail server uses a sum of heuristics like SpamAssassin. Maybe use Hashcash. But for mailservers that reject your email before even receiving it, you have no chance.

If you want your emails to get through, your best bet is to relay your email through a reputable mail service. Many ISPs offer this for free; look for SMTP access. If your ISP doesn't offer this, there are plenty of commercial services.

Alternately, originate mail from a non-dynamic IP address. Buy a static (commercial) IP address from your ISP, or set up a VPS such as on Linode.

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Ultimately this is what I did, I send to gmail and have a forward to my other email on rules. It's a ugly hack but works for what I need. – Eric Leschinski Nov 14 '12 at 13:19

Hotmail (Windows Live) blocks the emails of domains without an SPF record. You have to jump through some hoops with Microsucks and make a profile with your domain and maybe they let your emails through.

Ugly work around to send automated email from my personal computer to hotmail

What I ended up doing was emailing my gmail account and then having gmail forward emails with a rule to my hotmail account using these commands:

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You could try using a mail proxy (They forward your message on and that way it appears to be from a more legitimate source than a residential DHCP address).

Actually it's coming back to me now (It's been a while since I did this). You can edit the Sendmail M4 configuration and add some lines like this:

Define      define(`SMART_HOST', `')dnl     
Feature     FEATURE(`authinfo',`hash /etc/mail/authinfo')dnl    

I think you may have to recompile after that but it's fairly easy to do.

This will allow your mail to relay through your ISP's mail server so it appears more legit to the outside world (No longer coming from your dynamic IP!). I started using gmail and for email a couple years back so haven't done it for a while but Google around and you'll find some more info on how to do it.

Some info here:

The m4 > bit is when it recompiles I think.

Also, you need to have an account on your ISP's mail server and that account is then used to forward on your home server's mail to the outside world. I used to do this all the time until my ISP shut me down by blocking port 25 on my service. Now I use gmail apps and, you can host your domain's mail through them for free so is a pretty nice alternative to actually hosting your own mail.

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