First things first
- Update your Mac to the latest macOS. iCloud Mail accounts require OS X 10.7.5 or later.
- Go to the System Status page and check iCloud Mail.
If you still need help, try the steps below for your issue.
If you can't access iCloud Mail at iCloud.com
- Make sure that you're using a supported browser. Use these steps to update Safari. If you're using a different browser, check its help to learn how to install updates.
- Clear your browser's cache. In Safari, choose Safari > Clear History. If you're using a different browser, check its help for steps.
- If you can access iCloud Mail from a different location or Internet connection, contact your Internet service provider or network administrator. Some Internet configurations intentionally or unintentionally prevent access to certain websites or services, such as iCloud Mail.
If you can't send mail from the Mail app on your Mac
Use these steps if your message can't be delivered, you're attaching a large file, or the recipient didn't get your message.
If you receive an alert when you send a message from your @icloud.com email address using Mail on your Mac
“This message could not be delivered and will remain in your Outbox until it can be delivered. The reason for the failure is: An error occurred while delivering this message via the smtp server: server name.”
- Open Mail and choose Mail > Preferences.
- Click the Accounts tab.
- Select your iCloud email account.
- Click the Account Information tab.
- Choose your iCloud email account from the Outgoing Mail Server (SMTP) menu. If you choose Edit SMTP Server List, you won't see your iCloud SMTP server as an option.
If you're attaching a large file
Message attachments can't exceed the maximum size allowed by your email service provider or the recipient's email service provider. The maximum size varies by service provider. Try using Mail Drop, compressing the file before sending it, or sending your message without the attachment.
If your recipient doesn't receive your message
- If an “unknown address” or “undelivered mail returned” message appears in your Inbox after you send a message, go to your Sent mailbox and make sure that the recipient's email address is correct.
- If you're using macOS Mail or accessing your iCloud Mail using Safari or another supported web browser, check your Drafts, Sent, and Outbox mailboxes:
- If you see an unsent copy of the message in Drafts, try to send it again.
- If you see the message in your Outbox, make sure that you're connected to the Internet and use the steps above to select the iCloud SMTP server.
- Ask the recipient to check their Junk mail folders or mailboxes.
- If your recipient still doesn't receive your message, but your message was sent without any alerts or “undelivered mail” messages, your message might have been blocked or filtered by the iCloud Mail servers or the recipient's mail server. To find out, contact iCloud Support. You should also ask your recipient to contact their email administrator.
If you can receive messages but can't send them
Your Internet service provider might be blocking the protocol used to send email (SMTP) across their network. Contact your service provider and ask about SMTP traffic that crosses their network to an external service, such as iCloud. If your service provider blocks SMTP traffic, ask them how you can be exempted from SMTP blocking.
If your service provider isn't blocking SMTP traffic and you still can't send messages, contact Apple Support for help.
If you can't receive mail in the Mail app on macOS
Find the name of your iCloud email account on the left side of the main Mail window. If your account name is dimmed and has a lightning-bolt symbol next to it, your account is offline. To take your account online, connect to the Internet, then choose Mailbox > Take All Accounts Online.
If you still can't receive email, get more help with your Mail app.
If you need help sending or receiving mail on your iPhone, iPad, or iPod touch
- Make sure that you're connected to the Internet. Try to open apple.com in Safari on your iPhone, iPad, or iPod touch.
- Go to iCloud.com on a Mac or PC to see if you can receive email for your iCloud email.
- Tap Settings > [your name] > iCloud and turn on Mail on your iPhone, iPad, or iPod touch. If you're using iOS 10.2 or earlier, go to Settings > iCloud.
- Make sure that new data is pushed to your device automatically:
- On your device with iOS 10 and later, tap Settings > Mail > Accounts > Fetch New Data and turn on Push.
- On your device with iOS 9 and earlier, tap Settings > Mail, Contacts, and Calendars > Fetch New Data and turn on Push.
- Then send an email to your account to see if Push is working.
- Go back to Fetch New Data. Then Tap your iCloud account and turn on Push. If you have multiple iCloud Mail accounts, you can use Push with one account at a time. Make sure that Push is turned on for your primary iCloud Mail account.
- Turn your device off and back on.
If you still can't send or receive mail, turn off each of the settings in steps 3, 4, and 5 above, then turn them back on.
If you need help using iCloud for Windows
Get more help
Use these steps if you need help sending or receiving email in the Mail app on your Mac.
If you still need help, contact iCloud Support.