Telnet smtp auth. com ehlo myworkstation 250-zcs723.

Telnet smtp auth. com ESMTP Postfix helo myworkstation 250 zcs723.

• Telnet smtp auth contoso. In the admin console, under the MTA tab, you see two options: Enable Authentication in the admin console and reload postfix you will then see the AUTH line when you do the telnet test above and AUTH will say LOGIN and PLAIN. zohomail. 4 Unrecognized authentication type bye. The client issues an AUTH command, naming a specific mechanism. Needless to say, Telnet bore witness to one of the first # apt-get install telnet sasl2-bin Using telnet command we will connect to SMTP server. Scroll down to Telnet Client, check the box next to it and press the OK button. com at port 587 via telnet as: . You can use the TELNET command to test and Take note of the line that reads ‘250-AUTH NTLM LOGIN’. In If your SMTP server requires and support basic authentication (and it's enabled), you can still send emails via telnet. net. com And this was the output I got: 250-smtp. LOGIN Others are not supported. In the File menu, click on Account Settings and then select the option that is also named Account Settings. You need a program, of which s_client is one option. 12. 97. com. To initiate an SMTP connection with a server via Telnet, use a command specifying the server’s address (domain name or IP address) and the port it listens on. xxx. It needs to be converted to base64. force9. 32. com 25 But it says T 250-AUTH=LOGIN. Once you're sure your receive connector is configured make sure your email client is configured for authentication as well for the SMTP server. austin. 3. If using Office365 SMTP server i. I'm trying to connect to yahoo smtp server by : telnet smtp. 33 Connected to www. However my server shows this output: 250-mail. io 2525 To connect to an SMTP server by using Telnet on port 25, you need to use the fully qualified domain name (FQDN) (for example, mail. This makes it easy to simulate a mail client with the telnet command to check the access to port 25. com 25 Use the HELO command to tell Open a telnet connection. Incorrect configuration in Azure AD or Exchange Online can prevent successful SMTP authentication. You can connect to a SMTPS server (which In this article. 4b) Encrypted Password. Type of abuse Harassment is any behavior intended to disturb or Type “telnet”, hit Enter. com server. To do this, open a command prompt or terminal window and telnet to our SMTP server like this (note customers of vISPs other than Plusnet should amend the server address accordingly e. Time to log in! The previous output listed the AUTH command and the available mechanisms SMTP Authentication improves the trust between a customer's mail server and Essentials to eliminate the risk of spoofing. 1). We are attempting to use telnet to track messages in our test . Cause Working Safe and Easy. To verify that remote SMTP server is reachable to you, open shell prompt and type: telnet smtp. 220 zcs723. example. openssl s_client -starttls smtp -4 -connect smtp. com 250-server. Type “open mail. bommtempo. As soon as you connect to the server, run: ehlo example. Use existing mailfrom For non-secure SMTP, you can use. After this I tried to send an email without 1st authenticatingi was able to, multiple timeswhich lead me back to the SMTP setup pageand when I set the config today (after a reboot of the host and VM) it worked. com 250-sandbox. rr. Adding -4 to my openssl command line forced IPv4 negotiation and it succeeded. I am trying to send an email through telnet using a SMTP server through Telnet. 501 #5. From there, you can follow the normal progression for sending email through SMTP. com) and 25 is the port number used by the SMTP service. By cyberx86 Just a random guy who dabbles with assorted technologies yet works in a completely unrelated field. The AUTH command sends the clients username and password to the e-mail server. net if you're a Force9 customer, relay. Configure SMTP authentication on your mail servers using the SMTP-AUTH login command by following these step-by-step instructions and examples. In our case, we run a local SMTP server. com 250-PIPELINING 250-SIZE 10240000 250-VRFY Using Telnet with an SMTP Server. You should receive a reply like "220 mail. com at 465 port - I don't see any thing. If you're using Windows, make sure you have Telnet-client programm installed. net over the chosen port is open and that your API key is valid. 220 MailServer. Here are SMTP commands that you can try using telnet to test email. free for this issue I added my account via POP3 and SMTP in outlook 2016 it works fine and also I test it via power shell and It works fine too, the issue is in telnet when I use auth command I get the bellow message: AUTH 504 5. > telnet mail. Attempt to send a test email without authentication. AUTH Use Putty/Telnet to connect to the remote SMTP server and issue commands manualy. Normally, this should only be done for testing reasons. com Below is a classic telnet sequence against a SMTP server : $ telnet 127. The command may, optionally, contain some authentication data. Understanding the SMTP Auth Login This document describes how to use telnet to perform a basic SMTP test from your local client through a configured listener on your Email Security Appliance (ESA) or Security Management Appliance (SMA). Learn more about SASL mechanisms, ports, and errors associated with SMTP AUTH. redhat. Hint: You can issue several commands just prefix them with a different sequence number (A1, A2, A. 1 Connected to localhost. 220 dhcp. com Microsoft ESMTP MAIL Service ready at Wed, 24 May 2017 12:58:07 +0300 The major manual and command-line method for testing GSSAPI-based authentication with an SMTP server is “SMTP AUTH GSSAPI Telnet”. 1 Connected to 127. 109 (162. com ehlo myworkstation 250-zcs723. Using a Base 64 encoder such as this one, encode your user name and enter it. Please make sure mail from is not root@localhost. If you haven't built your own SMTP client yet, you can test this using TELNET. I just wanted to simulate the SMTP connection on my Windows XP command line, and when I telnet smtp. 125. The first thing If you want to test authenticated SMTP, you need to have the ‘AUTH LOGIN’ command available. Setting up Telnet varies across different operating systems. I have Basic authentication and Integrated Windows authentication both enabled SSL/TLS is a complicated cryptographic protocol with most of the data in binary; there is no way you will be able to do your end manually using the telnet program which is only designed to handle text plus a few "terminal" controls that don't exist in SSL/TLS (nor SMTP). SendGrid’s software allows developers to specify custom handling instructions for email using an X-SMTPAPI header inserted into the message. com:25 openssl s_client -starttls smtp -connect example. POP3 and IMAP4 clients. First, connect with your SMTP server using Telnet: Understand the roles of SMTP and Telnet, and discover step-by-step instructions for setting up and using Telnet to ensure your email system's reliability. And replace the default port 25 if necessary), hit Enter. Below are the steps to email via Telnet: 1. 137. server. You may need to use openssl to provide security before the server makes a plain auth method available. office365. The ubiquitous Secure Shell (SSH) protocol, which uses encryption and supports key-based authentication, was in fact designed to supplant Telnet itself. For instance: telnet sandbox. com 25” (replace YourDomain. com 25 Trying 10. YourDomain. com ESMTP Sendmail 8. Below are instructions on how to test SMTP AUTH against a mail server using Telnet and entering the commands by hand. 0) Pre-requisite – Get Your Base64 Encoder. 4a) Encrypted Username. I want to send mail using SMTP. Next, enter your base64 encrypted password. 220 hostname. Let’s use telnet to check if an SMTP server is running on port 2525: $ SMTP Authentication is an "extension" in SMTP terms, so it requires server and client to use EHLO verb for greeting to indicate support for extensions, as opposed to the obsolete HELO greeting. 92-10-25. For instance: This command attempts to connect to the From time to time you may find that you need to verify email user authentication in a client-agnostic way. Despite having been around for a long time, (SMTP Service Extension for Authentication) Published January 27, 2011. com:587 -crlf -ign_eof – SMTP authentication protects your mail server from unauthorized use. 28] 250-SIZE 35882577 250-8BITMIME 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-PIPELINING 250-CHUNKING 250 How to communicate with an SMTP server with telnet, in order to send a mail? telnet smtp. This process can be invaluable for testing and verifying the server’s capability to handle email transmission. net 250-8BITMIME 250-PIPELINING 250-SIZE 31457280 250-AUTH PLAIN LOGIN 250 AUTH=PLAIN LOGIN. If you need a TLS connection before login just replace your telnet command with : openssl s_client -starttls imap -connect localhost:143 SMTP I want to use telnet to google mail server on linux. 69 #1 Tue, 04 Aug 2009 19:37:10 -0300 DEBUG: Recv: 220-We do not authorize the use of this system to transport unsolicited, DEBUG: Recv: 220 and/or bulk e-mail. io 2525 220 sandbox. NET application to access the SMTP server. 3) SMTP Auth Login Plain. 7. How to enable SMTP AUTH in Outlook. com 250-mx. Using bare Telnet sounds like a pretty brittle approach; you really want to use a proper SMTP client to talk to the SMTP server. io Hello 250-SIZE 37748736 250-PIPELINING 250 TELNETセットアップ. 2. [10] For backward compatibility, HELO greeting may be accepted when no extension is used. Using telnet or openssl is a great way to test and debug connection issues. Type ‘telnet’ to run telnet; Run the following A1 NO [AUTHENTICATIONFAILED] Authentication failed. com with your SMTP server's domain or IP address, and 25 with the appropriate port number if it's This is my first time using telnet; I'm using it to debug PHPMailer. 10 On most SMTP servers you will get a list of commands back when using the Extended Hello (EHLO) command: 250-smtp. 1) Launch Telnet from a Cmd Prompt. Categorized as Software, Systems Admin Tagged email, postfix, smtp, telnet. smtp. Skip to main content. Here's what I get when logged in: EHLO localserver. 2. com with your domain name. when I try to authenticate myself on server using my yahoo mail ID and password. Getting this far indicates that your connection to smtp. To get Telnet operating: 1. 16384 ready at Thu, 16 Feb 2017 16:28:00 +0100 EHLO telnet to smtp server and run 'EHLO hostname' command. Follow the step by step instructions below to send an email on Linux using Telnet. 9600. SMTPサーバーからの応答を確認するのに、メールクライアントでは分からないので「TELNET」という機能を使うと便利です。Windowsの場合には「Windowsの機能の有効化または無効化」から Using Telnet with an SMTP Server. You can also use Telnet to manually connect and test the Office 365 SMTP server: Connect to smtp. sendgrid. Topics for Exchange SMTP Auth Login. Telnet is available in Windows 10 but it isn’t activated. com Hello localserver. com Hello 32. com ESMTP ready My request is : ehlo smtp. The sasl2-bin package contains gen-auth command which we will use to generate our BASE64 encoded response to server’s authentication challenge. This opens a pop-up window. Type “AUTH LOGIN”, hit Enter. View all of This section illustrates the NT LAN Manager (NTLM) Authentication: Simple Mail Transfer Protocol (SMTP) Extension with an example scenario in which an SMTP client successfully authenticates to an SMTP Connected. I am using this command. Contribute to clayrisser/telnet-mail development by creating an account on GitHub. 1] 250-SIZE 157286400 250-PIPELINING 250-DSN 250-ENHANCEDSTATUSCODES 250-STARTTLS 250-8BITMIME 250-BINARYMIME 250-CHUNKING 250 SMTPUTF8 AUTH Sending an Email via Telnet Sending an email through an SMTP server using Telnet involves a series of commands and interactions. TELNETセットアップ. 250-PIPELINING. com 25 The response from server is : Trying 98. 105. com Hello [1. For example, if you send the EHLO command to smtp. ; Choose your account and click on Change. But I'm not able to use TLS and authenticate to Gmail's SMTP server using command line (or Here's what I've tried with PLAIN authentication mode, both using telnet and openssl: telnet www. com 587 indicated it tried to use an IPv6 address to communicate. Using Telnet to Test SMTP Connectivity. telnet smtp. Now you can pass this base64 encoded string to the FYI @ScottStensland in trying this today I found the command seemed to hang up, and using plain telnet smtp. gmail-smtp-in. Replace smtp. mydomain. omniservice2. com Microsoft ESMTP MAIL Service ready at Sat, 15 May 2021 19:22:41 +0000 EHLO EC2AMAZ-GODJD 250-abc. 86. com) or the IP address of the Sometimes I need to test if a particular machine is able to send e-mail via an SMTP server. Lets’ start by using telnet command to connect to our server: $ telnet 10. relay. com, you will find that it currently Step-by-Step Guide to Test SMTP with Telnet Step 1: Open a Telnet Session. I am in the process of writing an application that sends mail via an valid GMail user ID and password. PLAIN is for SASL PLAIN. com 587 And typed: EHLO smtp. mail. com Hello [::1] 250-SIZE 37748736. Therefore, our domain name is localhost. If you get 235 Authentication succeeded response then your connection to your account’s SMTP server is established and your SMTP2GO Username and Password are valid. localdomain (127. I don't know how to combine user name and password. . ; Select More Settings. com 25 Trying 1. outlook. 250-BINARYMIME. com ESMTP Postfix helo myworkstation 250 zcs723. 4 Unrecognized Authentication Type" response. AUTH LOGIN) to choose an Here's a screenshot of telnet smtp. The capitalized text after the AUTH command is a list of the types of authorization that All I did is connected to smtp. io ESMTP server ready EHLO example. The following steps are required on a Linux command line: Execute telnet SERVERNAME 25. domain. I saw many thread about sending email using Telnet, but I couldn't do that. mailtrap. Do the same for your password, which is requested next. You may also try to send a test message as below: mail from: 250 OK rcpt Testing SASL Authentication through SMTP. com on port 587 using Telnet or OpenSSL. com (162. And after that convert it to base64 and then send. 0. 220 abc. The following process explains how you can perform such a test. com:587. 4) I am using AUTH PLAIN mechanism. When I type in EHLO or usual Take note of the line that reads ‘250-AUTH NTLM LOGIN’. For AUTH PLAIN authentication I can use this string that is the username and password If your SMTP server supports unencrypted authentication you can use telnet, e. mymailserver. 5. 5) Sending Email. gmail. 4 Connected to mail. xxx Connected to smtp. We can use the telnet command to check an SMTP connection. Here are the basic SMTP telnet commands How to Use Telnet to Test SMTP Communication | Microsoft Learn there is also a list of responses listed for you with explanations. it 25 Trying 94. 25. Try. 10. Authentication Login Required Workaround You May Perform The Following The Steps In Order To Send Out The Email By Using SMTP Authentication. AUTH LOGIN is advertised as supported in the response to the EHLO command, but when I'm trying to send AUTH LOGIN to the server, I'm getting "504 5. 250-DSN. 138. 220 www. Share. I think it goes something like: AUTH NTLM <bae64encode something> 334 <bae64encode someth 如何利用 Telnet 測試 SMTP AUTH 首先，要先取得SMTP server授權帳號與密碼的Base64字串Linux系統可以使用Perl指令，Windows可以使用Powershell，或是也可以在git bash上使用Perl指令。 Perl 1perl -MMIME::Base64 -e 'print encode_base64("username&quo And the debug result of the PEAR Mail code is: DEBUG: Recv: 220-orion. This is also described here and here. This connects telnet to port 25 on the server with the name SERVERNAME. my. I am trying to send Email using telnet and smtp. yahoo. 3. 1], pleased to meet you EHLO server. This feature simply creates an SMTP AUTH username and password pair in Essentials that customers can enter on their email exchange server to authenticate with Essentials. 3 AUTH not Some smtp server requires authentication. The best thing about telnet is that it's an almost universal tool, and that it allows you not only to test an SMTP server but also other services like POP, IMAP, etc. com launch telnet with automatic authentication disable (on mine it is telnet -X SRA) feed its input with the commands you want to pass; wait some delay before entering input, at least for login and password, because if you don't telnet clear input before reading and discards your inputs; Here is an example that allowed me to telnet to my own machine : If SMTP authentication isn't working for you then you can test it from a command line using a program called Telnet. Click on Turn Windows features on or off. Then, type AUTH LOGIN followed by your base64 encrypted username and hit enter. com 587: I searched and found many links including Wikipedia's article about STARTTLS command. SMTP is a plain text protocol. 2) Type One Word: ehlo. Escape character is ''^]''. 108: Connection timed out Trying 2404:6800:4003:c02::6c telnet smtp. 4 Invalid arguments to AUTH command 501 Unknown command XXX 501 Unknown option XXX 501 Unknown value XXX 503 #5. LOGIN is one of authentication methods and it does not have variations. We didn't need to implement the NTLM protocol, as SamDecrock's httpntlm already did the hard work. com [92. blabla. In Exchange 2007/2010/2013 you would need to enable ExchangeUsers permission group as well as an authentication mechanism such as Basic authentication. com at your service, [14. To begin testing the SMTP server, open a terminal on your Linux system and initiate a Telnet session to the SMTP server. 250 CHUNKING. com 110 Trying 10. 32 Connected to zcs723. the server gave me Error; 501 malformed auth input (#5. When I give my password, it fails. But if I try AUTH LOGIN via Telnet, gmail Getting Telnet. hope this helps! jitensh (JitenSh) May 3, 2018, 1:58pm 5. telnet alt4. AUTH LOGIN translates to basic authentication. swaks is designed for smtp server testing. The server will respond with the ESMTP extensions that it supports, including AUTH. SMTP client email submissions (also known as authenticated SMTP submissions or SMTP AUTH) are used in the following scenarios in Office 365 and Microsoft 365:. Stack Exchange Network. Telnet test is quite different for SMTP AUTH. View all of auth login And you will receive the following: 334 VXNlcm5hbWU6 This is the word "Username" encoded in Base 64. Click on Turn Windows features on or Telnet can be used to test SMTP AUTH by using above encoded string # telnet 127. with crentials right? use As you can see, especially if you’re a developer looking to add email-sending functionality to your application, SMTP AUTH client submission more or less takes the cake. com on telnet it does not work because authentication is mandatory and many times it is not possible to make authentication work in Telnet Start >> Enter Powershell; Right-click on Windows PowerShell >> Run as Administrator Issue Sending SMTP Authentication Using Telnet Symptoms Sending Email By Not Using Any Email Applications. A blank command window with title Telnet smtp. But it is not able to do so. com 25 The server will reply with 220 smtp. somewhere 53 Trying 10. 250-8BITMIME. 11 When you echo a string you include a newline, but the newline should not be included in the credentials you pass in to SMTP AUTH. AUTH can be combined with some other keywords as PLAIN, LOGIN, CRAM-MD5 and DIGEST-MD5 (e. com:465 openssl s_client -starttls smtp -connect example. 177. What do I have to do after? What do I have to write after "HELO"? Very briefly, the way SMTP authentication works is as follows: The server advertises a number of authentication mechanisms in response to the client’s EHLO command. Send Emails using Telnet. Report abuse Report abuse. it Microsoft ESMTP MAIL Service, Version: 8. If you don’t Authentication process testing: It plays a key role in testing SMTP authentication processes, which are vital for the security and integrity of email communication. it. com 25. localdomain [127. EXAMPLE. Step 2: Establish a TCP connection (port 25) with the SMTP server using telnet smtp. Email clients and servers frequently perform GSSAPI authentication automatically and behind the scenes in real-world circumstances, enabling users to send emails securely without having to directly deal with the I'm failing at finding the commands I need to send to authenticate to a SMTP server using NTLM. connect to address 74. The mail server will respond with 235 Authentication successful. To install Telnet on your Windows Device (7, 8, 10): Once you receive Response code 250 as above, type auth login and Enter. Authenticate yourself. g. If you want to test authenticated SMTP, you need to have the ‘AUTH LOGIN’ command available. telnet example. Your telnet window should look like the following now. For Auth testing, its been a while but i believe used this method How to Test SMTP AUTH using Telnet. com 250-PIPELINING 250-SIZE 10240000 250-ETRN 250-STARTTLS 250-AUTH PLAIN LOGIN 250-AUTH=PLAIN Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Ok I used the instructions from MS for telnet. I can connect but AUTH LOGIN gets me the following: 504 5. 243. 27. For instance, this server supports both NTLM and basic authentication. Improve this answer. Type telnet mail. l. 1. Follow If this is something that you have to test once in a while, or just for a small number of SMTP servers, then telnet may be the most convenient tool, as it has been pointed out. net ESMTP Postfix EHLO dummydummy 250-hostname. But, there is somthing else, smtp server sometime doesn't accept mailfrom with root@localhost. To install Telnet on CentOS, Fedora, AlmaLinux, and Red Hat: $ sudo dnf install telnet To install Telnet on Arch Linux and Manjaro: $ sudo pacman -S inetutils Send email using Telnet. 10; Wed, 24 Mar 2004 13:03:57 -0500 hello test 250-dhcp. and want to know which authentication mechanisms the server Credentials are correct and they are normal Windows authentication username/password and they are correctly used by all our . 32] 250-SIZE 52428800 250-8BITMIME 250-PIPELINING 250-AUTH PLAIN LOGIN 250-STARTTLS 250 HELP AUTH LOGIN 334 Maybe. 109)) 250-AUTH LOGIN PLAIN 250 SIZE 53477376 Following this tutorial, I try logging in via AUTH LOGIN. ; Applications, reporting servers, This commands can be executed on Linux and Windows. Since SendGrid offer 100 free emails everyday, we will send emails using the SendGrid STMP server. br ESMTP Exim 4. smtp. The AUTH Command The AUTH command is an ESMTP command (SMTP service extension) that is used to authenticate the client to the server. Type Telnet into the search field in the toolbar at the bottom of your desktop. 220 smtp. For instance, this server Getting Telnet. somewhere. 162. com 25 where "mail. ) IMAP authentication with TLS. com This means the SMTP session has begun. com" is the name of the Simple Mail Transfer Protocol (SMTP) server of your email provider (such as smtp-server. After connecting to your server on port 587, type ehlo yourdomainname. Because the username and If you're interested, most of the change was actually in a sub-sub-project (smtp-connection), and the forks of nodemailer, nodemailer-smtp-pool, and nodemailer-smtp-transport are only necessary to get my smtp-connection fork to be picked up. AUTH LOGIN PLAIN does not mean that server supports LOGIN PLAIN variation. remote. These protocols only allow clients to receive email messages, so they need to use authenticated SMTP to send email messages. Escape character is '^]'. printf '%s' '[email protected]' | base64 and similarly for the password. First, telnet to your mail server: $ telnet mail. Different authentication method. 10/8. 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. 1 25 Trying 127. 11 25 Trying 10. The first thing you need to do is get a base64 To initiate an SMTP connection with a server via Telnet, use a command specifying the server’s address (domain name or IP address) and the port it listens on. We can use telnet to test and debug if a particular machine is able to send e-mail via an SMTP server. 68. ♠. 250-AUTH GSSAPI NTLM. 4 Unrecognized authentication type. ” I'm trying to send an SMTP Email to SendGrid using Telnet and getting "535 Authentication failed: The provided authorization grant is invalid, expired, or revoked" as a response when I enter my base64 encoded API Key. And that is as far as I got. yourserver. Port 587 is While hand testing SMTP servers by hand is possible and viable, using a tool designed for this will be much easier. com opens with cursor. 250-ENHANCEDSTATUSCODES. This article explains SWAKS. com 25 If server is reachable and SMTP service is listening port 25 you will see prompt looking like this: To find out what authentication mechanisms an SMTP server supports, send the EHLO command. For secure SMTP, you can use one of following: openssl s_client -starttls smtp -connect example. 250-mail. To do this you will be required to encode login and telnet sandbox. tururu. Supports attachments, authentication and encryption! Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Code: Select all esx2:~ ajcody$ telnet zcs723. com Simple Troubleshooting For SMTP Via Telnet And Openssl Resolution First - Understanding Your Authentication Requirements In ZCS. SMTPサーバーからの応答を確認するのに、メールクライアントでは分からないので「TELNET」という機能を使うと便利です。Windowsの場合には「Windowsの機能の有効化または無効化」から Sometimes I need to test if a particular machine is able to send e-mail via an SMTP server. something. Type “HELO”, hit Enter. google. So, credentials encoded in base64 are surely correct but after entering them, I am prompted DONE and the connection is closed and the shell returns. 250-STARTTLS. Stack Exchange network consists of 183 Q&A We are attempting to use telnet to track messages in our test environment but we can not figure how to correctly input AUTH NTLM username/password string. 21 Connected to smtp. ; In the Here are the scenarios where you may want to use Telnet to test SMTP communication to or from the transport servers that exist in your Microsoft Exchange organization: If the connector allows Basic authentication, you need a utility to convert the text strings that are used for the username and password into the Base64 format. test smtp, imap and pop3 with telnet. Use Telnet to send your first SMTP email. ehlo I'm trying to authenticate myself against GMail SMTP Server by using the LOGIN authentication mechanism. com Hello localhost. Below is the full run Telnet works if the SMTP server is Office365 MX record. net 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN SMTP Protocol Basics. e. snuwv mchpuf qbkc nyjkv qbtxj twltr ndaauco xxssa devm ramncuk