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Resolved Question

Email that has 127.0.0.1 as it's IP Address

Aug 14, 2011 8:18AM PDT

Hello, some one I know sent me an email with the IP Address, 127.0.0.1. I did an Arin.net search and it says that it's a IANA Special Use.

What does this mean? Why would he send me an email address with that ip address?

Discussion is locked

MessyDesktop has chosen the best answer to their question. View answer

Best Answer

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This can be proper.
Aug 14, 2011 8:33AM PDT

Some email scanners use that address. Not to dive too deep here but for years you would see that when the email is scanned by the antivirus.
Bob

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Why an email scanner?
Aug 14, 2011 10:04AM PDT

So this person used an email scanner to send me an email?

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Sorry
Aug 14, 2011 10:14AM PDT

Since the return IP address is not reliable and can be spoofed then it means nothing. I offered one reason and it's just one besides the fact you can't use that IP address today.

Consider this one of the ways a person can remain anonymous.
Bob

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Proxy?
Aug 14, 2011 11:16AM PDT

So basically, they used a proxy to email me, is that it?

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Never mind
Aug 14, 2011 11:48AM PDT

I made a mistake. Thanks for answering.

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No that's not how it works
Aug 14, 2011 10:01PM PDT

I assume you have an anti-virus scanner installed and that it is set up to scan incoming emails.

If so, then it works like this. The AV interrupts the process between the download of the email and the display of it in your email software. it grabs the email and places it in some holding pen location on your computer, then scans it. If all is well, it releases it for the email software to display it.

But by saving it on your hard disk temporarily, the email software then sees that it has come from 127.0.0.1 which is your own computer.

The email software then inserts that final 'sent from' path into the route the email took to get to your computer.

I hope that helps explain it.

Mark

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Yes. That's it.
Aug 15, 2011 11:11AM PDT

But today because of spoofing even if you did get a look at the raw email header, it means nothing.
Bob