Email Connection Troubleshooting
Email Connection Troubleshooting for PressedMail.
Use this guide when IMAP or SMTP tests fail, a mailbox does not sync, or sending fails for a connected provider.
Four failure points, in the order the connection meets them.
First checks
- Confirm the mailbox works in provider webmail.
- Confirm IMAP is enabled and the provider allows app passwords or OAuth.
- Check host, port, username, encryption, and password exactly.
- Ask the host whether outbound SMTP and IMAP ports are blocked.
- Try a local test mailbox before changing production mailbox credentials.
PressedMail supports password or app-password connections and Microsoft OAuth. Google OAuth is disabled in the current Published build. Yahoo, iCloud, and Proton Mail remain coming-soon options and cannot be selected in the public setup flow.
Authentication Failed
Possible causes:
- The normal account password was used instead of an app password.
- The app password was copied incorrectly (extra spaces or missing characters).
- Two-step verification is not enabled, so no app password can be issued.
- IMAP is disabled by the provider.
- SMTP AUTH is disabled for the mailbox or tenant.
- Google OAuth is required but unavailable, or Microsoft tenant consent blocks the available OAuth flow.
- The account is blocked because of suspicious login activity.
- The wrong username format was used (for example, name only instead of the full email address).
- The app password has expired or was revoked.
Resolve by generating a fresh app password, enabling the provider's required security settings, or asking an administrator to allow the connection method.
Connection Timed Out
Possible causes:
- A hosting firewall blocks the port.
- A Docker container cannot reach a host service (for example, Proton Bridge on
127.0.0.1). - The DNS hostname resolves incorrectly.
- The mail server is unavailable.
- Outbound connections are restricted by the hosting provider.
Resolve by asking the host whether outbound ports 25, 465, 587, 993, and 143 are open, and by confirming the hostname resolves from the WordPress server.
TLS or certificate errors
Possible causes:
- The wrong hostname was used (it must match the TLS certificate).
- A self-signed certificate is not trusted.
- The certificate has expired.
- The certificate does not match the mail hostname.
- STARTTLS was selected on a port that requires implicit TLS.
- SSL/TLS was selected on a STARTTLS port.
PressedMail validates certificates and does not allow disabling certificate validation. A certificate error must be fixed at the configuration or server level, not bypassed.
Incoming Mail Works But Sending Fails
Possible causes:
- SMTP authentication is disabled.
- The wrong SMTP port was used.
- The sender address is not authorized for the SMTP login.
- The provider blocks aliases.
- The hosting provider blocks outbound SMTP.
- The SMTP username differs from the IMAP username and was entered separately.
Sending Works But Incoming Mail Fails
Possible causes:
- IMAP is disabled at the provider.
- The wrong IMAP hostname was used.
- The app password does not have the required IMAP/mail permission scope.
- Yahoo, iCloud, or Proton Mail was selected even though the public setup flow still marks it coming soon.
- Mailbox access is restricted by organization policy.
Messages or folders appear duplicated
This is usually provider label behavior, not a sync error:
- Gmail exposes labels as IMAP folders, so the same message can appear under several labels (Inbox, All Mail, a custom label).
- Archive and All Mail behavior can show the same message in multiple views.
- Providers use different aliases for Sent, Trash, Spam, and Archive folders.
- Multiple folders may refer to the same underlying message.
PressedMail maps provider special-use folders to standard roles. If a message appears in more than one place, confirm whether the provider uses labels before treating it as a duplication bug.