> For the complete documentation index, see [llms.txt](https://help.activenow.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.activenow.io/en/communication/message-delivery-statuses.md).
# Checking If a Message Reached a Participant
If a client says they didn't receive an email or SMS, you can verify it quickly in the communication history. ActiveNow logs every message sent, along with its delivery status — so you can see exactly whether it arrived or where it got stuck.
## Email communication history
Go to *Communication → E-mails history*. Each message shows a delivery status on the right.
## Email statuses
* **Accepted for delivery** — the email has been handed off for sending. No further information is available yet. Messages stay in this status briefly after being sent.
* **Delivered** — confirmed that the email reached the recipient's mailbox.
* **Temporarily undelivered** — the email was rejected by the recipient's server but will be retried automatically.
* **Delivery failure** — the email was permanently rejected. This usually happens when the address doesn't exist. Invalid addresses are automatically blocked to reduce this error.
{% hint style="info" %}
A participant says they didn't receive an email? Read more [here](/en/communication/email-not-delivered-to-participant.md).
{% endhint %}
## SMS communication history
Go to *Communication → SMS.* You will see all sent messages with the date, recipient, content, and delivery status.
## SMS statuses
* **Delivered** — the message reached the recipient.
* **Sent** — the message was sent, but the operator hasn't returned a delivery report yet.
* **Accepted** — the message was accepted by the operator for delivery.
* **Not delivered** — the message did not reach the recipient. The most common cause is an incorrect phone number.
* **Expired** — the operator attempted to deliver the message, but the recipient's phone was switched off or out of range during all delivery attempts.
{% hint style="info" %}
A participant says they didn't receive an SMS? Read more [here](/en/communication/sms-not-delivered-to-participant.md).
{% endhint %}
---
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