Mail setup on your own domain, DKIM, SPF, email quality check

A common issue with email on your own domain is that emails may end up in the "Spam" folder, reducing the likelihood that clients will read them. To solve this problem, it is important to configure mechanisms such as DKIM and SPF and use tools like Mail-tester and MxToolbox.

1. What is DKIM?

DKIM (DomainKeys Identified Mail) is a method of electronic signature for outgoing messages that allows receiving mail servers to verify that an email has not been forged or altered during transmission. The signature is added to the email header, and the recipient's mail server can use the public key published in the domain's DNS records to verify the authenticity of the email.

Benefits of DKIM:

• Increases trust in your domain.
• Reduces the likelihood of emails ending up in the "Spam" folder.
• Protects clients from phishing attacks and fraudulent emails.

2. Setting up DKIM involves several steps:

1. Generating DKIM keys:

•    Many email providers, such as Gmail, Yandex, and Mail.ru, offer the option to generate private and public keys.
•    The private key is used to sign emails on the server, while the public key is used to verify the signature on the recipient's side.

Example of DKIM signature in Yandex360:

2. Adding a DKIM record to DNS:

•   Add a text (TXT) record to your domain's DNS zone. The format of the record will look like this:

     default._domainkey.yourdomain.com IN TXT "v=DKIM1; k=rsa; p=public_key"

3. Verifying DKIM functionality:

•    Send a test email and use verification tools such as Mail-tester to ensure that the DKIM signature is working correctly.

3. Configuring SPF

SPF (Sender Policy Framework) is an email authentication mechanism that helps prevent sender address spoofing. It allows recipient servers to verify that an email was sent from an authorized IP address listed in the domain's DNS record. This is important for increasing trust in your emails and reducing the likelihood of them ending up in the "Spam" folder.

How to set up SPF:

• Adding an SPF record to DNS: create or update a TXT record in your domain zone's DNS. Example record:
  yourdomain.com IN TXT "v=spf1 ip4:IP_address_of_your_server include:_spf.provider.com ~all"
  v=spf1 indicates that this is an SPF record, ip4:IP_address and include: specify the permitted sources for sending emails, and ~all indicates a soft fail (use -all for a strict fail).

• Checking the configuration: use tools like MxToolbox to verify that the SPF record is correctly configured.

4. PTR record (or Reverse DNS)

A PTR record is a DNS record that links an IP address to a domain name. It is used by mail servers to verify the authenticity of the sender. If the recipient server cannot find a corresponding PTR record for the sender's IP address, this may increase the likelihood of emails ending up in the "Spam" folder. Configuring reverse IP through a PTR record confirms that the specified IP address truly belongs to your domain and is used for sending emails. To check if the PTR record is correctly configured, use tools like MxToolbox (read more about it below), which provide detailed reports and recommendations for problem-solving.

5. What is Mail-tester and how to use it?

Mail-tester is a convenient online service that allows you to check how your email will be perceived by mail services. It analyzes the email and provides a score based on many factors, including DKIM, SPF, the presence of text in the email, and more.

How to use Mail-tester:
1. Go to Mail-tester.com and get a generated test address.
2. Send an email from your email client or SMTP server to the specified address.
3. Follow the link in Mail-tester and get a detailed report with a score.

6. MxToolbox: a powerful diagnostic tool

MxToolbox is another essential tool that helps diagnose and troubleshoot issues with email configuration. It can be used not only to check for the presence of correct DKIM, SPF, and DMARC records but also to monitor blacklists and check the status of mail servers.

Using MxToolbox:

• Checking DNS records: enter your domain on the MxToolbox.com website and select DNS record lookup to ensure that DKIM, SPF, and DMARC are correctly configured.
• Blacklists: use MxToolbox to check if your IP address is listed in blacklists, which may affect email deliverability.
• Diagnostic reports: MxToolbox provides detailed reports, allowing you to easily identify issues and get recommendations for solving them.

7. Useful tips for setting up email

• Configuring SPF: Make sure to set up SPF (Sender Policy Framework) to confirm that email sending is authorized from your domain.
• DMARC: Additionally, use DMARC for extra verification and to establish policies for handling emails that fail DKIM and SPF checks.
• Regular testing: Check your email settings using Mail-tester and MxToolbox to identify and resolve potential issues.

Proper DKIM configuration and the use of tools such as Mail-tester and MxToolbox significantly increase the chances of your emails landing in the recipients' "Inbox." These measures help improve domain reputation, ensure the reliability and security of your mailings, and create a positive user experience for clients.