• Q: When I am trying to send email from command line, an error message appears: "An established connection was aborted by the software in your host machine". What is the problem and how can I fix it?
  • A: This error message is returned when connection is terminated by software which is running on host computer system, i.e., SMTP server. It can be caused by firewall or some other software.

If it is impossible to send email from command line using febooti Command line email tool for Windows (or using any other SMTP mail client), try connecting SMTP server with telnet (what is telnet?) client which is generally not blocked by firewall software. Read below the basic information on how to telnet SMTP server and make sure if it responds adequately and is available for SMTP client software.

Note for Windows Vista users. You have to install telnet client, otherwise, error message will be displayed:

  • 'Telnet' is not recognized as an internal or external command, operable program or batch file.

How to telnet SMTP server? To access telnet console, click Start button on the taskbar, choose Run..., enter telnet in input line and click OK. In telnet console window enter ? for list of supported commands. Note that open command syntax requires entering server host name and port number.

For connecting to SMTP server, type o smtp.server.com 25 (when trying to email from command line without indicating port number, febooti tool uses port 25 which is regularly listened by SMTP). Note, that smtp.server.com should be substituted with the actual server address to which email from command line is sent.

Alternative way of connecting to SMTP console through telnet client is to run DOS prompt (click Start, click Run, enter cmd and click Ok) and enter the following string: telnet smpt.server.com 25.

If connection has proceeded successfully, server should return code 220 with server address, greetings, mail server software version and / or another information. Enter one of the following line. Note that while in telnet it is not allowed to use backspace or make any corrections in telnet console command line. If a mistake is made while typing commands, line should be retyped without making any corrections.

  • helo testing
  • helo <your computer name>

If configured and operating correctly, SMTP mail server should respond to this command with code 250 followed by some additional information which may include server name, ip address and / or greeting.

If these procedures return a positive result in aforementioned manner, SMTP server is accessible, thus unability to email from the command line is likely caused by firewall settings. If the firewall is on local machine and user has adminstrator's access, try allowing febooti Command line email for Windows in firewall settings.

Otherwise, if user has not access to firewall (which might be caused due to either non-administrator account on local machine or firewall being located on remote hardware), network administrator or Internet Service Provider should be contacted on issue of unability to email from the command line particularly or, which is likely the case, on unaccessibility of SMTP server for any mail client software.

Note that not only classic firewalls, but also some antispyware and antivirus software products do their own minor "firewalling" which generally should not impact sending email from the command line or accessing SMTP server in standard way, however user should verify all security settings in these applications if necessary.

This febooti Command line email article may be referenced as (KB ID: 514).

Please do not hesitate to contact our support department with any possible further questions or to solve practical issues connected with Command line email. The solution will be provided shortly by e-mail and eventually added to FAQ.