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141

Because 74.125.235.55 isn't the MX (mail exchange) for gmail.com. If you ping gmail.com, ping uses the A record to perform its task, but sending emails (often) incorporates other servers. You can use the tool dig (on Windows: nslookup -q=mx gmail.com as grawity mentioned in the comments) to see those DNS records: Probe:~ trurl$ dig -t ANY gmail.com ; ...


29

Most people are shocked to hear this, but email is not actually guaranteed to ever reach the intended destination. It might fail for a variety of reasons. It could simply fail to arrive (for several reasons) or could be getting redirected to the recipients spam folder for some reason. If you think an email hasn't been delivered, you should send it again. ...


25

When you send email to user@domain.com, the outgoing mail server uses the DNS MX record of the destination domain to determine which IP address is responsible for handling mail at that domain. This may not be the same IP address returned during a normal ping. Using the 'dig' tool on Linux I can determine that the MX record for gmail.com resolves to the ...


16

mailx can use SMTP. It's configure file is ~/.mailrc One example is mailx using Gmail's SMTP. The configure can even be in one command: mailx -v -s "$EMAIL_SUBJECT" \ -S smtp-use-starttls \ -S ssl-verify=ignore \ -S smtp-auth=login \ -S smtp=smtp://smtp.gmail.com:587 \ -S from="$FROM_EMAIL_ADDRESS($FRIENDLY_NAME)" \ -S smtp-auth-user=$FROM_EMAIL_ADDRESS ...


12

Try to use: email@[74.125.235.55]


11

There is nothing 100% that you can use to prove on your own. If you had your own mail server, you can show outgoing logs - however, they can be falsified. You can use read receipts, but again, they can be falsified. The best bet is if you use a third party mail server that is impartial, and they can provide logs, that should stand as proof. You may have ...


10

No, it is not required to set up a DNS cache on the server. The server should use a caching DNS resolver that's somewhere nearby, but most hosting companies already run their own resolvers for the entire datacenter and configure servers to use them by default. By default, both Postfix and Dovecot use local accounts for everything. If you have a Linux ...


8

You do need a special SMTP server, but you don't need to set it up yourself. As somebody has already suggested, you can create a bogus Gmail account and use the SMTP for that. Or, for really anonymity, you can use a SMTP provider; this will allow you to forge your return address (the same way spammers do) for an extra layer of anonymity and customization ...


8

The first thing to make clear when asking "is ABC safe?" is to define your threat model. In this case, you have (and kudos for that): your threat model is your ISP being malicious and wanting to look at your (outgoing, presumably, since you ask about their SMTP server) e-mails. Against such a threat model, using the ISP's mail server does indeed present ...


8

http://www.ehow.com/how_4614939_check-why-email-was-delayed.html It is a common misconception that email delivery is instantly completed. Email is designed to be sent from Mail Server to Mail Server until it reaches the ultimate destination with no guarantee on how long it will reside at each intermediary stop. Most cases of delayed email ...


7

74.125.235.55 is not a Gmail gateway. If you go direct yourself to the IP address in your browser it won't go to the Gmail website; it'll go to Google, so that could be one point.


7

As Wes said, it's possible, depends of the server's level of security. Below is a classic telnet sequence against a SMTP server : $ telnet 127.0.0.1 25 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'. 220 hostname.server.net ESMTP Postfix EHLO dummydummy 250-hostname.server.net 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN ...


7

Normally, mail and derivatives (and almost any other Unix MUA) use the traditional sendmail interface - /usr/bin/sendmail, provided by almost all MTAs (postfix, exim, sendmail, courier). This is the traditional Unix way. Once a message is submitted through sendmail, your MTA handles message transmission. Depending on configuration, it may either connect ...


7

Any business that wants to accept incoming email over the internet will need an SMTP server, so that facebook has one isn't unexpected. It is an incoming server, so won't accept facebook source addresses. It appears to be fairly standard, and wants standard headers: # telnet 66.220.155.11 25 Trying 66.220.155.11... Connected to 66.220.155.11. Escape ...


6

Despite other assertions, ISPs can triviallly intercept any email you send through their servers - in fact they systematically do this all the time - for example by using spam filters (which are legit). They also almost certainly log metadata - including from address, to address, date at minimum. That said, SMTP is not a secure protocol and can be ...


6

If you only want it running on port 587 (and I'm not sure you do; I'd think you'd want it running on both 25 and 587), then find the line in /etc/postfix/master.cf that looks like this: smtp inet n - n - - smtpd And change it to look like this: 587 inet n - n - - smtpd If you want ...


6

First, that IP address itself is not going to be listed as a DNS MX record (even if you used the mail server's correct IP address), as the others said, so it is not going to find the server in the first place (it is also not going to route based on that IP address as the @thedomain is just used for lookups). Even if you used telnet to connect to the server ...


6

SMTP isn't insecure, it perfectly provides the level of security it is designed to - which is none - it cannot be considered insecure as there is no security to subvert. A protocol can be considered insecure where it is designed to offer a level of security and fails to do so - WEP wireless security is an example of an insecure protocol. Semantics ...


6

In short - yes it is possible if you can connect directly to the recipients SMTP server. For the reasons "Rup" outlines it may not be especially practical, and if you are on a network behind a firewall you may not be able to get a connection to a remote server on tcp port 25 at all. Assuming this doesn't apply for you, then here is the detail: When you (as ...


5

Because of spam, most (if not all) ISP and email providers will not allow you to spoof an email using their SMTP servers. You will need to sign up for a hosted email package which will provide you with an SMTP server for use with your domain. The registrar of your domain may offer such a package. If not there are many hosting providers which offer email ...


5

This is a VERY important thing to be able to do and has saved my bacon on several occasions! So FOOEY to all those who voted down this question! PLEASE NOTE: I'm referring to the technical question, not the motive. Being able to do this is important for testing ones system, for example. Having the system up and therefore able to use an automated web-based ...


5

I wouldn't use the SMTP support in Mutt. <subjective> It's just not the Unix way. Much better is </subjective> to configure something like esmtp or msmtp or maybe nullmailer to relay email through Gmail's servers, and then let Mutt use the standard /usr/bin/sendmail way of sending messages.


5

Unfortunately, as with physical letters, proof of sending is not proof of receipt. While the e-mail shows as sent in your mail client and it will probably be shown as sent in your ISPs mail server, there will be (many) other mail servers between there and the final recipient. At each one of these the e-mail could have got lost or delayed, so it could well ...


5

There is a website called readnotify.com that will confirm if you have sent an email and that it will tell you if the email was opened or not. As an example, suppose you register your email jdoe@example.net with readnotify.com, ok, then if you were to send an email to jbloggs@example.com via readnotify.com, you can append at the end of the email address in ...


5

You can use the inet_interfaces directive in /etc/postfix/main.cf to control what address Postfix listens on for incoming connections. If you set it to the following it will only listen on the loopback interface, which means that connections can only originate from that machine. inet_interfaces = loopback-only


5

Yes, you can just install hMailServer or Mercury Mail to have a SMTP server. The big problem, however, is spam. Many (almost all) mail servers will block messages coming from residential connections, due to massive spam problems. Your ISP may be blocking all SMTP connections on port 25 as well, for the same reason. Most mail providers these days use SPF, ...


5

Maybe. You may need to use openssl to provide security before the server makes a plain auth method available. First you need to check what AUTH mechanisms are available. You can do that by passing the AUTH command with no arguments, to the pop server: $ telnet pop-server.example.com 110 Trying 10.10.10.10... Connected to pop-server.example.com Escape ...


5

Zero. It's trivially easy to spoof the from field to make it appear like the email came from someone else. DKIM is designed to provide authenticatation of mail servers, not individuals. The idea being that "valid" mail servers that normally send lots of emails (belonging to Google, Yahoo, etc) can be distinguished from spam mail servers.


5

Yes. The ISP is probably implementing "rate limiting" to thwart the efforts of spammers. Spammers don't like to be delayed because they are victimizing millions of recipients in as short a time as possible (it's a race against having their web site or other services shut down, so they want to get the maximum number of responses before the inevitable ...


5

The SMTP service uses port 25 by default. Secure SMTP (SSMTP uses SSL) uses port 465 by default. Although these are the defaults, pretty much every unused port number can be used. Most email clients will only try to connect to these ports unless instructed otherwise. These are the default email service ports: POP3: port 110 Secure POP3 (SSL-POP): port 995 ...



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