Troubleshooting transactional emails in Flexmail

Transactional emails are automated messages sent as a result of a specific user action, such as an order confirmation, account activation, password reset, or payment receipt. Unlike marketing emails, they prioritize speed and reliable delivery.

If your recipients are not receiving your emails or if the messages are ending up in the Spam folder, follow the troubleshooting steps below.

Why are my emails going to Spam?

A transactional email is usually marked as Spam for one of the following reasons.

A. Missing or Incorrect Email Authentication

Make sure the following DNS records are configured correctly:

• SPF
• DKIM
• DMARC

Even a single incorrect or incomplete record can negatively affect your email deliverability and increase the likelihood of emails being classified as Spam.

B. Poor Sender Reputation

Email providers such as Gmail and Outlook evaluate the reputation of both the sending domain and IP address.

Your reputation can be negatively affected by:

• high spam complaint rates
• large numbers of hard bounces
• sending emails to inactive or invalid email addresses

In these cases, even legitimate transactional emails may be filtered as Spam.

C. Content That Triggers Spam Filters

Certain characteristics of an email can increase the likelihood of being flagged as Spam:

• excessive use of links
• messages consisting mostly of images with very little text
• misleading or overly promotional subject lines

If you are experiencing deliverability issues, consider reviewing your email content using specialized email testing tools.

---

Why are recipients not receiving my emails?

If Flexmail shows the email as successfully sent but the recipient never receives it, check the following.

A. Incorrect Recipient Address

Verify that:

• the email address has been entered correctly
• the recipient's mailbox is still active

Invalid or inactive addresses are among the most common causes of delivery failures.

B. The Email Is in the Spam Folder

Ask the recipient to check the following folders:

• Spam
• Junk
• Unwanted Mail

In many cases, the email has been delivered successfully but has been incorrectly categorized by the recipient's email provider.

C. Strict Recipient Security Policies

Some mail servers, especially in corporate environments, apply strict security policies and may reject messages from new or low-reputation senders.

For testing purposes, send the same email to a personal Gmail or Outlook address to determine whether the issue originates on the recipient’s side.

D. DMARC or DKIM Configuration Issues

If the recipient uses a strict DMARC policy and your domain does not have DKIM configured correctly, the email may be rejected before it reaches the inbox.

---

Sender Verification and Configuration Checks

1. Has the Sender Address Been Verified?

Your sender address must be verified in Flexmail.

To check:

1. Go to Settings → Add or remove senders.
2. Make sure the address is marked as verified.
3. If it is not verified, complete the verification process using the verification email sent by Flexmail.

2. Are You Using the Correct SMTP Settings?

When sending via SMTP:

• use submission.flexmail.eu
• use port 587
• enable STARTTLS
• make sure you are using the SMTP credentials provided for transactional sending, not your Flexmail account login credentials

---

High Bounce Rate

If you notice a large number of bounces, it usually means that emails are being sent to addresses that:

• no longer exist
• contain errors
• have not been properly verified by recipients

It is recommended to:

• validate email formats when collecting addresses
• use verification procedures whenever possible
• promptly remove addresses that generate hard bounces

---

Useful tips

• Configure SPF, DKIM, and DMARC correctly before sending your first email.
• Use only verified sender addresses.
• Monitor bounce rates and remove invalid email addresses.
• Avoid content that resembles promotional or marketing emails in transactional messages.
• Ensure that transactional emails are used exclusively for user-triggered actions, such as password resets, order confirmations, and account activations. They should not be used for marketing campaigns or bulk email sending.

Read more here: Flexmail Knowledge Base