What is the difference between SMTP host and IMAP host?

SMTP (Simple Mail Transfer Protocol) is for sending emails. IMAP (Internet Message Access Protocol) is for receiving and syncing emails. For Mail AI to send replies, you only need SMTP. However, if you want sent replies to appear in your email client's 'Sent' folder, you can optionally configure IMAP for sent folder sync. This is a separate setting in Mail AI.

Why is my SMTP connection failing with 'Authentication failed'?

This almost always means incorrect credentials. Double-check: (1) Username is your full email address (e.g., info@yourdomain.com, not just 'info'), (2) Password is correct for that email account, not your cPanel login password, (3) You haven't exceeded your hosting provider's sending limits. Reset the password in cPanel if needed.

What port and encryption should I use for cPanel?

cPanel default SMTP settings: Port 465 with SSL encryption. Some servers also accept Port 587 with STARTTLS. Check your cPanel → Email Accounts → Connect Devices — it shows your exact settings. The most common mistake is using port 587 with SSL (should be STARTTLS) or port 465 with STARTTLS (should be SSL).

My hosting provider blocks outbound SMTP. What can I do?

Many shared hosting providers block outbound SMTP on ports 25, 465, and 587 to prevent spam. If you're getting 'Connection refused' or 'Connection timed out' errors, contact your hosting support and ask them to whitelist outbound connections on port 587 or 465 for your server IP. Alternatively, consider using Brevo or SendGrid which are designed to work from any hosting environment.

Can I use the same email account for both receiving and sending?

Yes. The email address you use for receiving (via forwarding) is the same one you configure for SMTP sending. Mail AI keeps these separate: forwarding brings emails in, SMTP sends replies out. Just ensure the email address in your Linked Email Accounts matches the FROM email in your SMTP settings.

How do I find my SMTP settings in cPanel?

Log in to cPanel → Email Accounts → find your email account → click 'Check Email' or 'Connect Devices'. cPanel shows a 'Mail Client Manual Settings' section with Outgoing Server details. Alternatively, most cPanel servers use: Host: mail.yourdomain.com, Port: 465, Encryption: SSL, Authentication: Yes. Username is your full email address.

How to Set Up Custom SMTP for AI Email Replies in Mail AI

If you host your own email (via cPanel, Plesk, DirectAdmin, or any hosting provider), Custom SMTP is how you connect it to Mail AI. This gives you full control over your email infrastructure — no third-party sending limits, no per-email costs, and your replies come directly from your own mail server.

This guide covers everything from finding your server settings to troubleshooting common connection issues. Most users complete setup in under 10 minutes.

🔵 When to use Custom SMTP: You have email hosting with your domain (e.g., [email protected]) through cPanel, Plesk, or a provider like GoDaddy, Bluehost, SiteGround, HostGator, or any shared/VPS hosting. If you use Gmail, Outlook, Brevo, or SendGrid, use their dedicated guides instead.

Custom SMTP Settings at a Glance

Your specific settings depend on your hosting provider. Here are the most common patterns:

Setting	Typical Value	Notes
SMTP Host	`mail.yourdomain.com` Copy	Often your domain with "mail." prefix
Port	`465` (SSL) or `587` (STARTTLS)	465 is most common for cPanel
Encryption	`SSL` (for port 465) or `STARTTLS` (for port 587)	Must match the port exactly
Username	`[email protected]`	Full email address, not just "info"
Password	Your email account password	NOT your cPanel login password
FROM Email	`[email protected]`	Same as username typically

⚠️ The most common mistake: Using the wrong username format. Always use your full email address as the username (e.g., [email protected]), not just "info" or your cPanel username. Also ensure port and encryption match — port 465 requires SSL, port 587 requires STARTTLS.

Step-by-Step Setup

1

Find your SMTP server settings from your hosting provider

Log in to your hosting control panel (cPanel, Plesk, DirectAdmin, or your provider's dashboard). Look for Email Accounts → your email address → Connect Devices / Mail Client Manual Settings. Copy the Outgoing Server (SMTP) hostname, port, and encryption type.
2

Verify SMTP is enabled for your email account

In cPanel, go to Email Accounts → Manage → Check if "Mailbox" is enabled. For Plesk, go to Mail → your domain → email address → ensure SMTP service is active. Some hosts disable SMTP by default — contact support if unsure.
3

Confirm your email account password

You need the exact password for the email account. If you don't know it, reset it in your hosting control panel. In cPanel, go to Email Accounts → Manage → Change Password. Use a strong password and save it securely.
4

Open Reply SMTP Setting in Mail AI

In your Mail AI dashboard, go to Linked Email Accounts. Find the email address you want to configure and click "+ Reply SMTP Setting".
Open Mail AI Dashboard →
5

Select Custom SMTP and enter your server settings

Choose Custom SMTP from the provider list. Enter your SMTP host (e.g., mail.yourdomain.com), port (usually 465 or 587), and encryption (SSL for port 465, STARTTLS for port 587). Enter your full email address as the username, the email password, and your FROM email and name. Then click Test & Connect.
Open Mail AI Dashboard →
6

Save and verify the connection

Mail AI tests the connection instantly. A green "Custom SMTP ✓" badge appears on your linked email card when successful. Your AI replies will now be sent from your own hosting mail server.
Open Mail AI Dashboard →

✅ Success looks like: Mail AI shows "SMTP connection successful" and your linked email card displays a green "Custom SMTP ✓" badge. Your AI replies will now be sent from your own mail server.

cPanel Quick Reference

📌 How to find your cPanel SMTP settings

Step 1:	Log in to cPanel (yourdomain.com/cpanel)
Step 2:	Go to Email → Email Accounts
Step 3:	Find your email account → click Check Email or Connect Devices
Step 4:	Look for Mail Client Manual Settings → copy the Outgoing Server details
Default cPanel settings:	`mail.yourdomain.com` • Port `465` • `SSL` • Full email as username

Popular Hosting Provider SMTP Settings

If you're unsure of your settings, try these common provider defaults:

Provider	SMTP Host	Port & Encryption
cPanel (generic)	`mail.yourdomain.com` or `yourdomain.com`	465 / SSL
Plesk	`yourdomain.com`	587 / STARTTLS or 465 / SSL
GoDaddy (cPanel)	`mail.yourdomain.com`	465 / SSL
Bluehost	`mail.yourdomain.com` or `box.yourdomain.com`	465 / SSL
SiteGround	`mail.yourdomain.com` or `smtp.yourdomain.com`	587 / STARTTLS
HostGator	`mail.yourdomain.com`	465 / SSL
DreamHost	`smtp.dreamhost.com`	587 / STARTTLS

Note: Replace yourdomain.com with your actual domain name. If these don't work, contact your hosting support for the exact SMTP settings.

Troubleshooting Common Custom SMTP Errors

"Connection refused" or "Connection timed out"

Your hosting provider may be blocking outbound SMTP connections. Many shared hosts block port 25, 465, or 587 to prevent spam. Try: (1) Switch to a different port (try 587 if using 465, or vice versa), (2) Contact hosting support to whitelist outbound SMTP for your account, or (3) Use Brevo or SendGrid as an alternative (these work from any hosting).

"Authentication failed" or "Username/Password incorrect"

Double-check: (1) Username is your FULL email address (e.g., [email protected]), (2) Password is correct for that specific email account (reset it in cPanel if unsure), (3) You're not using your cPanel login password instead of the email password. These are different.

"STARTTLS rejected" or "SSL handshake failed"

Port and encryption mismatch. Port 465 requires SSL encryption. Port 587 requires STARTTLS. If you're using port 465 but have STARTTLS selected, you'll get this error. Fix by matching the correct encryption to your port.

"Cannot connect to host" or "Unknown host"

Your SMTP hostname is incorrect. Common fixes: (1) Use mail.yourdomain.com instead of just your domain, (2) Use your domain without "mail." prefix, (3) Check if your hosting uses a different hostname like smtp.yourdomain.com or box.yourdomain.com.

"Sender address rejected: not owned by user"

Your FROM email address doesn't match the SMTP username. Most mail servers require that the FROM address matches the authenticated user. Ensure your FROM email in Mail AI matches the username exactly.

Emails are being sent but not appearing in my Sent folder

Mail AI only handles sending — it doesn't automatically sync sent emails back to your email client's Sent folder. To enable this, configure IMAP settings in Mail AI (optional). Go to Linked Email Accounts → your email → IMAP Settings → enter your IMAP host (usually mail.yourdomain.com), port 993, SSL, and the same username/password.

Custom SMTP vs Third-Party SMTP Providers

Feature	🔵 Custom SMTP	💚 Brevo	🟣 Amazon SES
Cost	Included in hosting	Free (300/day) or paid	$0.10/1,000 emails
Sending limits	Depends on host (often high)	300/day free, unlimited paid	Varies, can scale high
Setup complexity	Medium (needs server settings)	Easy	Advanced (DNS, sandbox)
Deliverability	Depends on host reputation	Excellent	Excellent
Best for	Existing email hosting, low volume	Custom domains, free tier	High volume, cost efficiency

💡 Pro tip: If your hosting provider has poor email deliverability (emails going to spam), consider switching to Brevo or Amazon SES. These services are optimized for transactional email and maintain excellent sender reputations, ensuring your AI replies land in the inbox.

Optional: Configure IMAP for Sent Folder Sync

If you want replies sent via Mail AI to appear in your email client's "Sent" folder (e.g., Gmail, Outlook, or webmail), configure IMAP in Mail AI:

IMAP Host: Usually same as SMTP host or mail.yourdomain.com
IMAP Port: 993 (SSL) or 143 (STARTTLS, less common)
Encryption: SSL (for port 993)
Username/Password: Same as SMTP credentials

When IMAP is configured, Mail AI will save a copy of every sent reply to your IMAP server's Sent folder. This is optional — your replies will send correctly even without IMAP configured.

Ready to Send from Your Own Mail Server?

With Custom SMTP connected, your Mail AI workflow uses your own email infrastructure: customer emails arrive, the AI summarises and drafts a reply, and when you click Send it leaves from your own email address via your hosting provider's mail server.

Go to your Mail AI dashboard →