Secure E-mail Exchange And Delivery Through SMTP Service

Overview of the functioning and advantages of SMTP services for businesses and individuals.

Simple Mail Transfer Protocol or SMTP is the method of handling e-mail exchange and delivery across IPs. To explain the process, when a user sends an e-mail to a colleague through any mail client, the outgoing server (SMTP) picks it. The server then communicates with the incoming server of the recipient (POP/IMAP).

The SMTP service provides a standard and reliable set of guidelines so that the servers can identify themselves and communicate efficiently. It helps identify the sender, recipient, where the content must go, etc. In other words, SMTP server ensures proper deliverability of the e-mail.

Most popular e-mail providers (Gmail and Outlook) have an associated SMTP host or SMTP server. Thus, they ensure high and efficient rates of delivery. However, a professional outbound SMTP service is specifically devoted to the message delivery process.

How SMTP Service Windows Work And Configuring An SMTP Server

Users can install an SMTP server on all versions of Windows server using the built-in tools. The SMTP server works as a mail relay service that sends and receives e-mails from many devices in the organization (scanners, access control devices, senders, etc.). Using the SMTP protocol, applications (web apps, SQL Reporting Services, SharePoint) can also send e-mails. The relay can also send e-mails to the Exchange servers such as Yahoo, Gmail, Office 365, etc.

For those people who use a windows cloud server, Microsoft includes a free SMTP service. However, users need to install it manually. Following are the steps to install it through Server Manager:

  1. In Server Manager, select Manage – Add Roles and Features.
  2. After clicking, Next
  3. Now, click Next until you get to the SMTP server page.
  4. Scroll down and check the SMTP server box.
  5. Check the box to include Management Tools and click on add features.
  6. Click next and at the end, click Install.
  7. The Microsoft SMTP is ready to use on your server.

Advantages Of Deploying SMTP Relay Service for Businesses

An SMTP service redirects the e-mails through third-party hosted accounts for e-mail delivery. Sending hundreds of e-mails to the customers is essential for every business. However, these bulk e-mails end up blocking the organization’s server because they clog the bandwidth. Deploying an SMTP relay service helps companies overcome these difficulties. Some other advantages include:

  • For organizations, SMTP Relay Service is very beneficial because it allows them to synchronize a Smarthost server. It means that if a business has 100 computers which use CRM, there is no need to configure the SMTP server on each machine. The enterprise needs only to synchronize the Smarthost server, which will manage all the e-mail accounts.
  • SMTP service is advantageous for organizations which use an e-mail marketing software. They will use certified IPS for executing e-mail campaigns. Additionally, they will get certifications like ISSP, several parallel SMTP connection channels, and automatic management of synchronous and asynchronous bounces.
  • An h offers guaranteed delivery of transactional and business e-mails using dedicated IP addresses. There is no blocking or tagging of these e-mails as spam.
  • Organizations can use the SMTP server to send e-mails to hundreds of recipients. It is a bonus for businesses since most Internet Service Providers (ISPs) limit access to their servers to avoid spam.

Google SMTP Service – Standard E-mail Transmission Protocol

Gmail is a popular e-mail client used by individuals and businesses alike. However, not many users are aware of Google’s portable SMTP server. All they need to do is configure Google’s SMTP server settings to whatever program or script they wish to send the e-mail from. All that the users require are:

  1. Gmail free account, or
  2. Google Apps account

The Google SMTP service has many benefits, which include:

  • It provides users with the Google Store option. They can index all the sent e-mails through their SMTP server.
  • The sent e-mails are backed up on Google’s servers and easily searchable.
  • Google’s SMTP server doesn’t use Port 25. Thus, it reduces the probability of an ISP blocking the user’s e-mails and classifying them as junk.
  • Those users who use their Gmail account for incoming e-mails as well, get the convenience of categorizing their mails at a single place.

However, as a policy, Google limits the number of e-mails a user can send through its SMTP server to 99 a day. Users get a fresh quota of 99 e-mails after every 24 hours.

Free SMTP Server List And Their Advantages

Due to its rapid adoption and ease-of-use, SMTP is the international electronic standard for transmitting e-mails. Thus, if you receive an e-mail, there is a 95% possibility that it is coming from an SMTP server. There are many popular free SMTP service providers, which include:


Gmail is a popular e-mail client, and Google provides an SMTP server to its users, free of cost. It also offers a paid plan which starts from $5 a month. The server offers the best deliverability rate for Gmail users.


The server is specially designed for transactional and marketing e-mail. The users get to send 40,000 e-mails for a month in the free version. Post this, and they need to upgrade the plan. It offers a secure cloud-based sending environment.

Other advantages of sendgrid include scheduling, A/B testing, segmentation, and other marketing features.


It is a robust and reliable service to send transactional e-mails and is beneficial for e-commerce businesses. In the free plan, it offers 2,000 e-mails to its users. The advantages include Split testing and comparative reports, optimized delivery infrastructure, etc.


It is a free SMTP service designed specifically for developers. MailGun is an e-mail automation environment which provides robust APIs for receiving, sending, and tracking the e-mails. The users get 10,000 e-mails a month in the free version. For those who require a higher quota, there are paid options available. Its advantages include E-mail Analytics, 30-day Logs, and quick mail delivery.


It is a cloud-based service which allows organizations to send marketing as well as transactional e-mails. MailJet ensures quick deliverability and is a powerful SMTP service provider. In the free plan, the users can send up to 6,000 e-mails a month. They can upgrade to the paid membership afterward. Its advantages include pre-designed marketing and transactional templates, e-mail statistics, and drag-and-drop e-mail editor.


It is ideal for businesses looking for web applications based transactional e-mails, service provider. Postmark team ensures high deliverability rates by manually reviewing every new account. It allows users to send 100 e-mails a month for free. Its advantages are highly compatible, responsive, well-tested, and nicely integrated templates. It also offers two-factor authentication to ensure the safety of user credentials.


E-mail deliverability is generally, not a problem unless a user needs to send bulk e-mails. Thus, for businesses who need to send important and transactional e-mails, an efficient outbound SMTP service is a necessity.