The best troubleshooting steps for Apple Mail not receiving emails start with checking your internet connection and confirming that your email server is active. Next, force-sync the mailbox and verify IMAP/SMTP settings and passwords in Mail account settings. Rebuild the mailbox to fix indexing issues, update macOS to avoid compatibility problems, and review Mail rules that may redirect incoming messages. Also ensure your iCloud or mailbox storage is not full. To prevent data loss during repeated issues, keeping an email backup with the SysInfo iCloud Backup Tool is a safe precaution.
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