Webmail works fine. You can log into yourdomain.com/webmail, see every message, send replies, no problem. But the moment you try to add the same mailbox to Outlook, Thunderbird, or your phone's Mail app, you get "cannot verify server identity," a password prompt that never accepts the right password, or mail that shows up on your laptop but not your phone. None of this means your mailbox is broken — it almost always means the client has the wrong server, port, or encryption combination. Here's how to get it right the first time, and how to fix it when it isn't.
Where to Find the Correct Settings
Don't guess at mail server settings and don't reuse settings from a different host. cPanel generates the exact values for your account, and the fastest way to see them is:
- Log into cPanel and open Email Accounts.
- Find the mailbox you want to configure and click Connect Devices (older cPanel themes call this "More" → "Configure Mail Client").
- cPanel shows the incoming and outgoing server, ports, and username for that exact mailbox, plus autoconfiguration links for Outlook and mobile.
If your domain's mail is proxied through Cloudflare or another CDN, ignore the orange-cloud hostname for mail — email doesn't go through the web proxy. The mail server is your server's actual hostname, usually something like mail.yourdomain.com or the shared hostname your host assigned (SkyServer shows this directly on the Connect Devices screen).
IMAP vs POP3: Pick One and Stick With It
This is the single biggest cause of "it works on one device but not another." IMAP and POP3 handle mail completely differently, and mixing them across devices creates exactly the confusion people run into:
| Protocol | How it behaves | Use it when |
|---|---|---|
| IMAP | Mail stays on the server; every device sees the same inbox, read status, and folders | You check mail from more than one device (almost everyone) |
| POP3 | Mail downloads to one device and, by default, gets removed from the server | You only ever check mail from a single computer and want a local archive |
If you've ever set up POP3 on your desktop first and then wondered why your phone shows an empty inbox, that's the mechanism working as designed — POP3 already took the mail. Switch everything to IMAP and this stops happening.
Recommended Ports and Encryption
These are the standard secure values for a cPanel mail server. Use SSL/TLS everywhere — there's no reason to run mail unencrypted anymore, and most hosts (including SkyServer) block or discourage the plaintext ports by default.
| Service | Port | Encryption |
|---|---|---|
| IMAP (incoming) | 993 | SSL/TLS |
| POP3 (incoming) | 995 | SSL/TLS |
| SMTP (outgoing) | 465 | SSL/TLS |
| SMTP (outgoing, alternate) | 587 | STARTTLS |
Username is always the full email address — you@yourdomain.com, not just you. This trips up more people than any other single field, especially when a client's "add account" wizard pre-fills just the local part.
Setting Up Outlook (Desktop)
- File → Add Account, and enter the full email address.
- If Outlook's auto-discovery finds the right server, let it. If it stalls or picks the wrong host, choose Advanced setup → IMAP and enter the settings manually.
- Incoming mail: your mail hostname, port 993, SSL/TLS.
- Outgoing mail: same hostname, port 465 (SSL/TLS) or 587 (STARTTLS).
- Under outgoing server settings, make sure "My outgoing server requires authentication" is checked, and set it to use the same credentials as the incoming server — this is the single most common thing people forget, and it produces a very specific symptom: mail arrives fine but nothing ever sends.
Setting Up Thunderbird
Thunderbird's account wizard is generally better at guessing correctly than Outlook's, but verify it before finishing:
- Account Settings → Add Mail Account, enter your name, full email, and password.
- When Thunderbird shows the detected configuration, click Manual config and confirm: IMAP, port 993, SSL/TLS, and authentication method set to Normal password.
- Confirm the outgoing (SMTP) entry separately — Thunderbird sometimes reuses a leftover SMTP server from a previous account. Under Account Settings → Outgoing Server (SMTP), edit or add an entry pointing at your actual mail hostname on port 465.
Setting Up iPhone or Android Mail
- iOS: Settings → Mail → Accounts → Add Account → Other → Add Mail Account. Android: Gmail app or the built-in Mail app → Add Account → Other/IMAP.
- Choose IMAP when asked. Enter the full email as both the username and email field.
- Incoming host: your mail hostname, port 993, SSL enabled.
- Outgoing host: same hostname, port 465, SSL enabled, and enter your credentials again when it asks for outgoing authentication — mobile clients treat incoming and outgoing as separate logins even though it's the same mailbox.
Symptom: "Cannot Verify Server Identity" or SSL Warnings
Cause: the client is connecting to a hostname that doesn't match the SSL certificate on the mail server — usually because someone typed yourdomain.com instead of the server's actual mail hostname, or the shared SSL cert only covers the host's own domain.
Fix: use the exact hostname cPanel's Connect Devices screen gives you, not a guess. If your domain has its own AutoSSL certificate covering mail.yourdomain.com, that's the safest value to use since it'll match cleanly on every device.
Symptom: Authentication Keeps Failing Even With the Right Password
Cause: almost always the username field. Clients love to pre-fill just the part before the @ sign, or auto-strip the domain during setup.
Fix: go back into the account's advanced settings and confirm the username reads the complete email address. Also rule out a stale cached password — on iOS and Android in particular, deleting and re-adding the account is often faster than trying to edit a broken one in place.
Prevention
- Always use IMAP for anything you check from more than one device.
- Copy settings straight from cPanel's Connect Devices screen instead of typing from memory.
- Use the full email address as the username everywhere, every time.
- If you ever migrate hosts, expect mail client settings to need updating too — the webmail login surviving a migration doesn't mean Outlook or your phone will keep working without a settings refresh.
Frequently Asked Questions
Why does webmail work but Outlook doesn't?
Webmail runs entirely on the server through your browser, so it never touches the IMAP/SMTP ports or SSL hostname matching that a desktop or mobile client relies on. A working webmail login only confirms the mailbox and password are correct — it doesn't confirm the client-side connection settings.
Should I use IMAP or POP3?
Use IMAP unless you have a specific reason not to. It keeps every device in sync because mail stays on the server. POP3 downloads and typically removes mail from the server, which is why a second device ends up with an empty or incomplete inbox.
What port should I use for outgoing mail?
Port 465 with SSL/TLS is the most broadly supported option on cPanel servers. Port 587 with STARTTLS also works and is what some ISPs prefer if 465 gets blocked on their network.
My mail arrives but I can't send anything — what's wrong?
Check that "outgoing server requires authentication" is enabled and set to use the same login as incoming mail. Many clients default this to off, which lets the account receive mail fine while every outgoing message silently fails or queues forever.
Can I use the same mailbox on my phone and laptop at the same time?
Yes, as long as both are configured with IMAP. IMAP is built for exactly this — both devices show the same folders and read/unread status because the mail lives on the server, not on either device.
