Create and send
Email deliverability (spam, bounce and sending failures)
What happens when an email doesn't arrive: how the platform records bounces, spam flags and blocks, where to see each case in the communication, what you can resolve on your own and what needs support. This is the #1 topic of so-called — this guide explains the real rules.
Concepts and terms
| Term | What does it mean |
|---|---|
| Bounce (return) | The recipient's server rejected the message. Hard bounce: definitive rejection (non-existent email, invalid domain) — appears as "Rejected by recipient's domain". Soft bounce: temporary failure (box full, server unavailable) — appears as "Not delivered". |
| Bounce blocking | Automatic protection: employees whose e-mail bounced will be skipped in future sends ("Blocked by bounce"). The blockage persists until removed by support. |
| Marking spam (complaint) | The recipient marked the message as spam. On the platform it appears with the label "Refused by recipient". |
| Sending failure (card) | Rejected submissions: failed attempt, domain rejection (bounce), employee removed, no email license and blocked due to bounce. |
| Not sent (card) | Contacts that did not receive it for some reason: invalid email/cell phone format, spam flag, not delivered (soft bounce), failed attempt and sending limit reached. |
| Sender | The "From" name/address of the email. Live in Settings → Email; creation involves domain configuration (DNS) and is done with support. |
| Reputation | The "grade" of the sender's domain/IP with providers. Too many bounces and spam flags lower reputation and make delivery worse for everyone — that's why mass unblocks are gradual. |
What can you see and do on the platform
- In the announcement details (General tab): Send Failed and Not Sent cards, each with CSV download listing the people and reason per line (e.g.: "Declined by recipient's domain", "Blocked by bounce…", "Sending limit reached")
- In the Views tab: the stage of each recipient (Sent / Received / Viewed) — anyone who does not appear with "Sent" has fallen into one of the cases above
- Force resend (card Not sent): reprocesses temporary failures — invalid format fixed, soft bounce, attempt failures. Does not reprocess definitive bounces, bounce blocking, spam marking or lack of license
- In Settings → Email: list, search and activate/deactivate existing senders
Step by step
Diagnose why someone didn't receive it
- 1.Open the announcement → General tab. If Send Failure or Not Sent is greater than zero, download the CSV of the card — each line has the employee and the reason.
- 2.Click on the Views tab (search for the person by name): the individual status confirms the stage at which you stopped.
- 3.Interpret the reason:
- "Refused by recipient's domain" → hard bounce: check if the email is correct in the employee's registration; If the company changed domains, update the database.
- "Not delivered" → soft bounce: usually resolves on its own; use Force Resend.
- "Blocked by bounce, please get in touch..." → the person is on the block list; correct/confirm the email and open a support ticket asking for unlocking (see below).
- "Rejected by recipient" → the person marked it as spam; don’t force resends — evaluate content/frequency for this audience.
- "Email or cell phone in invalid format" → correct the employee's registration and force the resend.
- "There is no valid email license" → account licensing issue; talk to support/CS.
Request bounce unblocking (via support)
- 1.Download the CSV of the Send Failed card (or ask support for the account's blocked list).
- 2.Confirm that the emails are valid (the person exists, the box works) — unblocking invalid emails generates new bounces and worsens reputation.
- 3.Open a support ticket with the list to be unblocked. Large lists are unlocked gradually (the team releases them in batches and monitors behavior) — it's protecting your domain's reputation, not bureaucracy.
- 4.Good practice recommended by the team: carry out a monthly analysis of blocks and send consolidated unblocking requests.
Add or change a sender (via support)
- 1.Ask support to include the sender (name + address).
- 2.If the domain is not yet configured, support sends the DNS document with the notes that your company's IT needs to create — domain authentication is what prevents it from falling into spam.
- 3.After configuration, validate with a test send.
- 4.If you want, the sender can be restricted to certain profiles/teams — ask for inclusion.
- 5.What you do yourself next: activate/deactivate the sender in Settings → Email.
Prevent delivery problems
- Keep the employee base clean (valid corporate emails; remove disabled) — imports with "delete unlisted" help keep the base loyal to HR.
- Avoid persistently resending to those who returned or marked spam.
- Prefer senders with an authenticated domain (configured via DNS with support).
- Track failure cards after each large send; bounce spikes indicate an outdated base.
Limits and rules (confirmed in the code)
| Rule | Detail |
|---|---|
| Bounce blocking | Automatic and persistent: valid for all future sends until unlocked by support |
| Force Resend | Reprocesses only: invalid format, spam marking*, soft bounce, failed attempt and limit reached. Never reprocesses definitive bounce, bounce blocking and without a license |
| Card "Sending Failed" | Attempt failed + rejected by domain + employee removed + unlicensed + blocked by bounce |
| Card "Not Sent" | Invalid format + rejected by recipient + not delivered + failed + limit reached |
| CSV vs card | The "unsent" CSV also includes pending/processing/awaiting follow-up — may be greater than the card number |
| Unlock | Does not exist in the interface — only via support call |
| Sender creation | Does not exist in the interface — only via support (the E-mail screen lists and activates/deactivates) |
\* Technically eligible for resending, but not recommended — resending to those marked as spam worsens your reputation.
What tends to confuse
- "Rejected by recipient" means spam marking — the label doesn't use the word "spam", but that's what it represents. "Refused by the recipient's domain" is a bounce (technical problem/address).
- Forcing a resend does not resolve bounces or blocks — in these cases, the solution is to correct the registration and ask support to unblock it.
- Bounce blocking does not expire on its own — without the call, the person will continue to be skipped in all messages.
- Mass unblocking is gradual on purpose: releasing thousands of addresses at once and having a new wave of bounces lowers the domain's reputation.
- "Receipt confirmation" at 0% does not mean bounce — this indicator depends on the sender's provider reporting delivery (see comunicados.md).
- The warning in the CSV "contact IT to unblock" refers, in practice, to opening a ticket with Comunica.In support (not to your company's IT).
When to contact support (summary)
| Situation | Who resolves |
|---|---|
| Unblock bounced employees | Support (called with list) |
| Add/change/delete sender; configure domain (DNS) | Support (+ your company's IT applies DNS) |
| Restrict sender to profiles/teams | Support |
| Total failure of a send / suspected incident | Support |
| Correct employee email, force resend, activate/deactivate sender | You, on the platform |
Related Features
- Communicados — metrics cards, error CSVs, and Force resend
- Employees — correction of registrations and database hygiene
- Email Channel — senders and domain configuration