Hello foregarts,
Thank you for reaching out to Apple Support Communities, and we'll be happy to help in any way we can. We understand you're having issues with sending iCloud Mail. Try the steps here to see if they resolve the issue: If iCloud Mail isn't working - Apple Support
"Things to check first
- Check the system status of iCloud Mail.
- Check that you turned on iCloud Mail:
- On your Mac, open the Mail app then choose Mail >Preferences. Click Accounts, then select your iCloud account in the sidebar. Under Account Information, make sure that the account is turned on and the status is online.
- On your iPhone, iPad, or iPod touch, go to Settings > [your name] > iCloud and check that Mail is turned on.
- Make sure you that haven't exceeded your iCloud storage limit. If you exceed your iCloud storage limit, learn how to make more space available in iCloud.
- Make sure that you're using the latest version of software on your device.
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
If you see an alert that says “This message could not be sent. It will remain in your Outbox until it can be sent.", make sure that iCloud is your Outgoing Mail Account.
- Open Mail and choose Mail > Preferences.
- Click the Accounts tab.
- Select your iCloud email account.
- Click the Server Settings tab. If iCloud isn't listed as the Outgoing Mail Account, select iCloud.
- If you choose Edit SMTP Server List, you won't see your iCloud account listed 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 you can receive messages but can't send them
Your ISP 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 ISP isn't blocking SMTP traffic and you still can't send messages, contact Apple Support for help. "
We hope this helps.
Cheers!
