Unable to Verify the Identity of the Server in Apple Mail

Apple Mail stops with unable to verify the identity of the server when a mail server shows a certificate that macOS cannot check. Self-signed certificates, wrong server names and expired certificates cause it, and Mail repeats that warning at every launch until you settle it. Below are Apple's trust steps for a verify server identity error, a hostname fix, a Keychain reset and a backup method to use before you remove an account.

Why does Apple Mail say unable to verify the identity of the server?

Apple Mail cannot verify server identity when your mail server uses a certificate signed by an unknown authority, such as a self-signed certificate. Apple's guide states that you can still connect, yet Mail warns you at every launch until you trust that certificate. Read Apple's page, If Mail can't verify a server's certificate, for that wording.

Hosting providers explain a second cause of Apple Mail verify server identity errors. Their support pages say a certificate fails when its name does not match your incoming server name. Typical triggers when Apple Mail cannot verify server identity:

• A self-signed certificate on your mail host.
• An incoming server such as mail.yourdomain.com while your certificate names a hosting server.
• An expired certificate on your mail server.
• Network devices that block SSL or TLS traffic.

Cause decides your fix for a verify server identity error, so read your certificate before you trust it.

How to fix unable to verify the identity of the server in Apple Mail?

To fix unable to verify the identity of the server, select Show Certificate in Mail's warning, check that its server name is yours and tell Mail to always trust it. These steps follow Apple's page, Trust a certificate in Mail.

1. In Mail's Verify Certificate window, select Show Certificate.
2. Read certificate details and confirm that its server name is your mail server. Do not trust a name you do not know.
3. Tick that box so Mail always trusts that certificate. Select Details to see current trust policies.
4. Select Connect or OK.
5. Enter your Mac account password when asked. For a root certificate, Apple says to enter name and password of an administrator on that Mac.
6. Send and receive a test email to confirm that Apple Mail no longer says it cannot verify server identity.

InMotion Hosting adds a detail for self-signed certificates. After you select Show Certificate, expand Trust and set Secure Sockets Layer (SSL) and X.509 Basic to Always Trust, then test incoming and outgoing mail. Its guide, fix Mac Mail verify server identity, shows that order for a Mac Mail verify server identity warning. To change trust later, Apple says to open Keychain Access.

How to fix a server name mismatch in Apple Mail?

To fix a mismatch that leaves Apple Mail unable to verify server identity, replace your incoming server name with your certificate's name. AccuWebHosting states that errors appear when a certificate does not match your server name in settings, and its fix swaps mail.yourdomain.com for a hosting server name. Your host publishes that name, so ask support if you do not know it.

1. Open Mail, select Mail in your menu bar, then Settings and Accounts.
2. Select your account, then Server Settings.
3. Enter your host's server name under incoming mail server. Use that same name for outgoing mail.
4. Confirm ports, since wrong ports also leave Apple Mail unable to verify server identity. IMAP with SSL uses 993, POP3 with SSL uses 995 and SMTP uses 465 or 587.
5. Save changes and send a test email.

AccuWebHosting's page, identity cannot be verified by Mail, lists these ports for iPhone and iPad. Mac Mail uses that same server and port logic. Menu names differ by macOS release.

What if Apple Mail keeps asking to verify server identity?

If Mail still asks, Always Trust did not save for its right policy. One Apple Community thread, Always trust an SSL certificate in Mail, has users who report prompts at every launch even after they tick that trust box. Replies in that thread suggest choosing that SSL option under that box. One user reports success after deleting bad certificates in Keychain Access, adding your root certificate again and choosing Always Trust from Mail's dropdown. That thread closed without a confirmed Apple fix, so treat these as user reports.

1. Open Keychain Access and search for your mail server name.
2. Double-click your certificate and expand Trust.
3. Set Secure Sockets Layer (SSL) to Always Trust.
4. Close that window and enter your password to save.
5. Quit and reopen Mail, then check mail.

If Apple Mail cannot verify server identity after that, your mail host must fix its certificate. Hosting guides agree on that last step: contact your administrator when settings and trust do not clear a verify server identity error. To keep a copy of your IMAP mail meanwhile, read how to download IMAP emails from a server.

Steps to back up your mail before you re-add your account

1. Install Corbett Email Backup Software on a Windows PC. It connects from that PC to your mail provider, not to your Mac.
2. Select IMAP Server or your provider, then enter your email address and password.
3. Tick folders to save. Inbox, Sent, Drafts and nested folders switch on or off one by one.
4. Choose MBOX for Apple Mail or Thunderbird, or PST for Outlook.
5. Select a save location, then start backup and watch live progress.
6. Open your log and CSV report to confirm folder totals.

That matters most for POP accounts, where mail can sit only on your Mac. With IMAP, mail also stays on your server. Test your backup in free demo before you buy. Lifetime licence starts at $99 with a 30-day money-back window. For another route from an IMAP host, Corbett IMAP Migration Tool moves mail from one account to another.

Which fix for unable to verify the identity of the server is best?

Match your verify server identity fix to its cause. Trust your certificate when you own that server. Change your server name when your certificate names another server. Reset Keychain trust when prompts return. Ask your host when an expired certificate causes that warning.

Can network settings cause a verify server identity error?

Yes. A firewall, proxy or security tool that inspects SSL traffic can swap your server's certificate for its own, and Mail then cannot verify server identity. AccuWebHosting lists DNS and blocked SSL or TLS traffic as checks. Test that same Apple Mail account on another network, such as a phone hotspot. If your error vanishes, your first network is its cause.

Update macOS if Apple Mail cannot verify server identity on every network, because system updates refresh trusted root certificates. To move mail to another account after you settle that error, see how to export GoDaddy email to Outlook.

Questions about Apple Mail server identity