Custom SMTP

Custom SMTP sends Zyelra outbound email through credentials you obtain from your hosting or mail provider. Zyelra does not host the mailbox and does not sync inbox mail over SMTP.

• Outbound only — no inbound mailbox sync.
• No Zyelra communications webhook for SMTP.
• You supply host, port, encryption, username, password, From, and optional Reply-To.

You need six values: Host, Port, Encryption (STARTTLS or SSL), Username, Password, and the From address you are allowed to send as.

Where to find them depends on who hosts your mail:

• cPanel / Namecheap / shared hosting — open Email Accounts (or Email Routing), create or select the mailbox, then open Connect Devices / Configure Mail Client / SMTP settings. Copy the outgoing server hostname (often something like premiumNNN.web-hosting.com), port 587 (STARTTLS) or 465 (SSL), and use the full email as username.
• Do not use mail.yourdomain.com if that hostname is proxied through Cloudflare — use the real mail-server hostname from the hosting panel.
• Google Workspace — prefer Connect Google in Zyelra (OAuth). SMTP AUTH / app passwords are an advanced alternative only when your admin enables them.
• Microsoft 365 — prefer Connect Microsoft in Zyelra. SMTP AUTH must be enabled by your admin if you use Custom SMTP instead.
• Cloud relays (SendGrid, Amazon SES, Brevo, Mailgun, Postmark) — create an SMTP user or API SMTP credentials in that provider’s dashboard. These usually work from Zyelra’s cloud servers when shared-host SMTP times out.

Confirm you have:

• SMTP host and port from the provider (not a guessed mail. subdomain).
• Username (often the full email address) and password or app password.
• A From address the SMTP account is allowed to send as.
• Optional Reply-To if replies should go somewhere other than From.

1. Step 1In provider

   Create or locate SMTP credentials

   In your hosting or mail provider, create an SMTP user (or enable SMTP AUTH / an app password). Copy the host, port, and whether TLS or SSL is required. Prefer app passwords over primary account passwords when available.

2. Step 2In provider

   Confirm the From address is allowed

   Ensure the From address you will use in Zyelra is authorized by that SMTP account (same domain / permitted sender list).

3. Step 3In Zyelra

   Open Messaging & Delivery → Email

   Go to Settings → Messaging & Delivery → Email and choose Custom SMTP.

4. Step 4In Zyelra

   Enter SMTP settings

   Paste host, port, TLS/SSL mode, username, password, From address, and optional Reply-To. Save the connection.

5. Step 5In Zyelra

   Test the connection

   Run Test connection / Test send. Confirm the message arrives and is not marked as failed auth.

1. Custom SMTP shows connected in Settings → Messaging & Delivery → Email.
2. Test send succeeds.
3. Failed messages show a clear auth or relay error rather than hanging.

• Authentication failed — regenerate the app password; confirm username is the full email if required by the provider.
• Connection timeout — Zyelra’s cloud API often cannot reach shared-hosting SMTP (cPanel/Namecheap). Prefer Managed Email, or a cloud SMTP relay (SendGrid, Amazon SES, Brevo). If you must use hosting SMTP, confirm the real mail-server hostname (not CDN-proxied mail.yourdomain.com) and any IP allowlist.
• TLS/SSL mismatch — try 587 + STARTTLS vs 465 + SSL as documented by your provider.
• Test timed out then send is blocked — edit/save Custom SMTP (or reconnect) so status is Connected, then use Managed Email or a cloud relay if the timeout persists.
• Username left blank when editing — editing keeps the existing password if Password is blank; re-enter Username if you changed it, or leave fields unchanged when you only update From details.
• Messages accepted but not delivered — check SPF/DKIM/DMARC at the DNS host for your From domain (outside Zyelra).