Why can I receive email but not send it?

Receiving and sending use separate connections. A mailbox can receive normally while its mail app has the wrong outgoing password, its sending service is not ready, or a particular message is rejected.

Start by finding out whether the problem affects one mail app, sending from Cedros too, or delivery to a particular recipient. Keep any error message and the time it appeared. Avoid repeatedly sending the same message while its status is uncertain.

Start with a small comparison test

1. Open Email → Inbox → New email in Cedros. Check From; use Change to select the intended mailbox if needed.
2. Add an outside email address you control to To and finish entering the recipient. Use a distinctive subject and a short message with no attachments.
3. Send it immediately. If a future time is selected, choose Send now instead. Let the Undo send countdown finish without undoing the message.
4. Check the outside account's inbox and spam folder. If it arrives, reply and confirm that the reply reaches Cedros.
5. If you also use a mail app, send a second short test from the same mailbox to the same outside account, with a different subject. Compare the results below.

If you cannot open the composer or select the mailbox, go to If Send is unavailable or the message is waiting below. Viewing old messages does not establish that receiving still works; use a fresh reply for that check.

What happens	Where to look next
The Cedros test arrives, but the mail-app test fails	The app's outgoing SMTP settings, credentials, and selected From address
Neither Cedros nor the mail app can send	The mailbox's sending service, account state, or provider error
Google Workspace sends from Gmail, but not from Cedros	The Google connection and sending access in Cedros
A small test arrives, but the original message does not	The original recipient, attachment, message size, or rejection notice
There is no error, but the message has not arrived	Scheduled time, Undo send, the app's Outbox, then recipient delivery checks

A message appearing in Sent is useful evidence, but does not prove that the recipient received it. Mail can be accepted for sending and then rejected or delayed later. Amazon SES explains the delivery process.

If only your mail app cannot send

These checks apply to Cedros-hosted mailboxes. For a Google Workspace mailbox, use the Google account connection instead of entering Cedros server details. See Choosing Cedros email or Google Workspace if you are unsure which service hosts your address.

1. In Cedros, open Email → Inbox → Settings → Your mail → Your addresses. Find the mailbox and select Connect mail app to retrieve its current connection details.
2. In the mail app, open that account's outgoing mail server or SMTP settings. Confirm that it uses the hostname shown in Cedros. Receiving settings alone do not configure sending.
3. Enable SMTP authentication. Enter the full mailbox email address as the username and its app password as the password, even if the app labels these fields optional. Use the same mailbox credential for incoming and outgoing mail; your Cedros sign-in password is different.
4. Use 587 with STARTTLS or 465 with SSL/TLS, matching the selected port and security setting. IMAP 993 with SSL/TLS is for receiving. Keep encryption enabled and resolve certificate warnings rather than bypassing them.
5. Check which outgoing server the account actually uses and the message's From address. Test with the mailbox's own address first. Receiving messages for an alias does not make every address at that domain an authorized sender.
6. Save the settings, reconnect the app, and repeat one small test. If it stays in the app's Outbox, read its error and check whether the app is offline or waiting to retry.

If you recently changed a password, update the separately saved SMTP password as well. Check whether the app password has expired or been revoked. If a replacement is needed, follow Creating, replacing, and revoking email app passwords; replacing every password is unnecessary for an ordinary problem with one connection.

A sender-address rejection can mean the From address is not assigned to the authenticated mailbox. Ask the administrator to check the mailbox and any explicit sending alias. A catch-all receiving rule does not authorize sending as every address it accepts. See Creating personal and shared email addresses.

For the app's account screens, use the guide for Apple Mail on Mac, iPhone or iPad, Outlook, or another mail app.

If a Cedros-hosted mailbox cannot send from Cedros either

Cedros-hosted mailbox messages require the native mail service's Amazon SES connection. Working incoming mail does not establish that SES is connected, the sending identity is verified, or the mailbox is ready to send.

Ask the site administrator to check the following. On a managed site, some provider controls may be handled for you; pass the error to the person responsible for the mail service if those controls are unavailable.

1. Confirm that the selected mailbox is Active and has finished provisioning. Also confirm that you have permission to send from it.
2. Open Settings → Site → Mail. Review Mail domain, including SES verified, and any warning in Mail service → SES outbound.
3. For a self-managed SES connection, open Settings → Providers → Email. Check the Amazon SES connection and that its provider record is active and connected. Follow Setting up outgoing email delivery to finish or repair the connection.
4. If the mail domain offers Finish SES setup or Retry automatic setup, use the outgoing-delivery guide to resolve the displayed setup problem. An identity and connection must use the appropriate AWS region; a verification completed in a different region does not resolve the current region's failure.
5. Once the mailbox, domain, and outgoing service are ready, repeat the small Cedros test and confirm receipt at the outside account.

Your sending contains personal signature and automatic-reply settings. It is not the SES connection. Changing the site's general email provider also does not replace the SES requirement for Cedros-hosted mailbox mail.

If a service warning remains, give the administrator its exact wording. Changing incoming MX records, turning off encryption, or repeatedly replacing app passwords will not repair an unavailable outgoing service. Use only the specific DNS changes requested by the relevant setup workflow.

If Google Workspace mail cannot send

Send one small test from the same Google account in Gmail. If it also fails there, give the error to your Google Workspace administrator; changing a Cedros app password will not repair that account.

If Gmail sends successfully but Cedros does not:

1. Confirm that the intended Google account is connected and that you are using the correct sending address.
2. Open Settings → Site → Mail → Other mail providers → Google Workspace and check the connection state.
3. If Reconnect is offered, follow Connecting your Google Workspace account and complete the requested Google authorization with the correct account.
4. Return to Email → Inbox, check From, and repeat the small test.

Reading or syncing Google messages does not by itself prove that the connection can send. A notice about syncing read, archive, or delete changes also concerns a different permission. If the connection appears healthy but sending still fails, report the sending error and the result of your Gmail test.

If Send is unavailable or the message is waiting

You can read the inbox but cannot send. Reading and sending are separate permissions. Ask the administrator to confirm your sending access and the mailbox's active state. The From selector only offers mailboxes available for sending; do not substitute an unrelated address to get past the restriction.

The composer asks you to correct a field. Finish adding at least one valid To recipient, correct invalid Cc or Bcc entries, and add a subject and message. Resolve any attachment warning before retrying. A validation error does not mean the sending provider rejected the message.

A future send time is selected in the composer. Choose Send now instead to clear the time, then select Send when the message is ready. Clearing the time does not send it. If it is already queued in Scheduled, follow Writing and scheduling an email to edit or cancel it. Allow the Undo send countdown to finish after sending; choosing Undo cancels that pending send.

The mail app still shows the message in Outbox. Read its current error and check connectivity, outgoing authentication, and the selected server. Before using Cedros to send a replacement, resolve or remove the app's pending retry so the recipient does not receive both copies.

If only some recipients or messages fail

Compare the failed message with the small test. Confirm the full recipient address, try without attachments, and check any rejection notice. If only one recipient is affected, ask them to check spam or quarantine and whether their mailbox can receive from other senders.

For Cedros-hosted mail using Amazon SES, the administrator may need to resolve a provider restriction:

• Recipient verification or sandbox restriction: In the SES sandbox, sending is limited to verified recipients or the SES mailbox simulator. Production access is regional and must be requested for the sending region; sender verification is still required afterward. Follow AWS's production-access instructions.
• Sending identity not verified: Check the sender/domain identity in the region used by the connection. A receiving mailbox can work while its outgoing identity is unverified.
• Quota, rate limit, or account paused: The administrator needs to check the SES account's current limits or sending status. Repeated retries will not remove a pause or an exhausted daily allowance.
• MAIL FROM domain not verified: Resolve the specific sending-domain DNS requirement reported by SES. This does not automatically mean your incoming mailbox's MX records should be replaced.

Use the exact error to select the remedy in AWS's SES error reference. Avoid changing unrelated provider or DNS settings simply because receiving and sending behave differently.

If sending was accepted but the recipient never sees it, check for a later bounce. Permanent recipient failures need a corrected address or recipient-side resolution; temporary failures can be retried by the delivery service. A missing message without an immediate error is a delivery investigation, not necessarily an app-password problem. See Amazon SES delivery outcomes.

Confirm recovery or get help

After correcting the identified problem, send one fresh message to an outside account you control, confirm that it arrives, and reply back. If you use a mail app, confirm both directions there as well as in Cedros. Use distinct subjects so old tests and automatic retries are easy to recognize.

If sending still fails, include the following in your support request:

• The affected mailbox and whether it is hosted by Cedros or Google Workspace.
• The mail app and device, if applicable, and the approximate failure time with time zone.
• The exact error or a screenshot with private content removed.
• Whether the test worked from Cedros, the mail app, and Gmail where relevant.
• Whether all recipients fail or only some, and whether a short message without attachments works.
• Any visible mailbox, connection, SES verification, or outgoing-service warning.

Do not include app passwords, provider credentials, or private message bodies. See Getting help and reporting a problem.