Hello there MidMarian71,
It sounds like you are unable to send email from your iCloud account on your MacBook. I want to recommend these steps from the article named:
iCloud: Troubleshooting iCloud Mail
http://support.apple.com/kb/ts4002
If you can't send mail in OS X Mail
- In OS X Mail, choose Preferences from the Mail menu.
- Click Accounts in the Preferences window.
- Select your iCloud account from the list of accounts.
- Click the Account Information tab.
- Choose your iCloud account from the Outgoing Mail Server (SMTP) pop-up menu. Examples: “Derrick Parker (iCloud)” or “smtp.icloud.com:derrickparker”.
Note: The Outgoing Mail Server (SMTP) menu also includes an Edit SMTP Server List command. If you choose this command, be aware that the iCloud SMTP server may not be among the servers that can be edited. This is expected behavior.If you're attaching a large fileMessage 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 compressing the file before sending it, or send your message without the attachment to verify that there are no issues with sending.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, make sure that the recipient's email address is correct. Go to your Sent mailbox and make sure that the email you sent was addressed correctly.
- If you're using OS X Mail or accessing your iCloud Mail (iCloud.com/mail) using Safari or another supported web browser, check your Drafts, Sent, and Outbox mailboxes:
- If there is an unsent copy of the message in Drafts, try to send it again.
- If the message appears in your Outbox, the message was not sent. You might be working offline or the outgoing mail server (SMTP) may be unavailable. Refer to the steps earlier in this section for details about how to select the iCloud SMTP server.
- Ask the recipient to check any Junk mail folders or mailboxes on their system. Perhaps your message was received but accidentally filtered.
- If your recipient still does not 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 and ask your recipient to contact their email administrator as well.
If you can receive messages but not send messages
Your Internet Service Provider (ISP) may be blocking the protocol used to send email (SMTP) across their network. Contact your ISP and ask about SMTP traffic that crosses their network to an external service such as iCloud. If your ISP has a policy of blocking SMTP traffic, ask them how you can be made exempt from SMTP blocking.
If your ISP is not blocking SMTP traffic and you're still unable to send messages, contact iCloud Support for help.
Thank you for using Apple Support Communities.
Cheers,
Sterling