> ## Documentation Index
> Fetch the complete documentation index at: https://docs.custral.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting

> Fixes for email that won't send, won't arrive, or won't thread.

## Overview

Most email issues fall into three buckets: **sending** (it won't leave Custral), **delivery** (it left but didn't reach the recipient), and **threading** (messages land in the wrong place). Start with the table, then follow the links for the deeper fix.

## Common issues

| Symptom                                              | Likely cause                                                         | What to check                                                                                                         |
| ---------------------------------------------------- | -------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------- |
| Email stuck in the **Outbox** / won't send           | The mailbox connection expired or was revoked                        | **Settings → Domains** → the mailbox → **Test connection**; reconnect if it reports a problem.                        |
| A **scheduled** send never went out                  | The mailbox was disconnected before the scheduled time               | Scheduled sends move back to drafts on failure, reconnect the mailbox and resend.                                     |
| Sent email **doesn't reach** the recipient           | Deliverability, SPF / DKIM / DMARC not aligned, or poor reputation   | Work through [Deliverability](/comms/deliverability/overview); confirm the sending domain is **Verified** and warmed. |
| Inbound email **doesn't appear** in Custral          | The channel isn't connected, or is still syncing                     | **Settings → Channels**. Confirm the mailbox is connected, then run **Test connection**.                              |
| Replies **start a new thread** instead of threading  | Missing reply headers, or the message was forwarded                  | See [How threading works](/comms/email/threading). Forwards start a new thread by design.                             |
| **Smart compose** or **AI writing** does nothing     | Turned off, or workspace AI usage is exhausted (common in sandboxes) | **Settings → Client Settings → Email composer**; try again later if usage is exhausted.                               |
| A **blocked sender** still reaches the inbox         | Blocking is per account (you blocked a different inbox               | **Settings → Blocked Senders**) the **Account** column shows which inbox each block covers.                           |
| Template sends with literal `{{tokens}}` in the body | No linked record, or the property is missing on it                   | Link a record before sending; unresolved tokens hold the send for review.                                             |

<Note>
  When reporting an issue, include the **request id** shown in the error toast. It links the in-app error to the server
  logs and makes it far faster to trace.
</Note>

## Related

* [Deliverability & domains](/comms/deliverability/overview)
* [How threading works](/comms/email/threading)
* [Email overview](/comms/email/overview)


## Related topics

- [Troubleshooting](/comms/sms/troubleshooting.md)