Apple mail only downloading full list on one computer

A frustrating issue!

It's possible that Apple Mail is only downloading the full list of emails on one computer due to a few reasons. Here are some troubleshooting steps to help you resolve the issue:

  1. Check your account settings: Ensure that your email account settings are identical on both computers. Go to Mail > Preferences > Accounts, and verify that the account name, password, and server settings are the same on both computers.
  2. Syncing issues: If you're using iCloud or another syncing service, check if the syncing is enabled and set to sync all devices. Go to System Preferences > iCloud (or your syncing service) and ensure that Mail is enabled and set to sync all devices.
  3. IMAP vs. POP: If you're using IMAP (Internet Message Access Protocol), it's possible that one computer is set to download emails locally, while the other is set to leave them on the server. Check your account settings to ensure that both computers are set to use the same protocol (IMAP or POP).
  4. Mailbox size: If one computer has a larger mailbox size, it might be downloading all emails to ensure that the mailbox is up-to-date. Check the mailbox size on both computers and adjust it if necessary.
  5. Cache and cookies: Clear the cache and cookies in Apple Mail on both computers. This might help resolve any issues with email downloading. To do this, go to Mail > Preferences > General, and click "Reset" next to "Reset Mailbox" and "Reset Cookies".
  6. Check for updates: Ensure that both computers are running the latest version of macOS and Apple Mail. Updates often resolve issues like this.
  7. Recreate the account: If none of the above steps work, try recreating the email account on the computer that's not downloading all emails. Go to Mail > Preferences > Accounts, and click the "+" button to create a new account. Enter the same account settings as before, and see if it downloads all emails.
  8. Reset Apple Mail: As a last resort, you can try resetting Apple Mail on the computer that's not downloading all emails. Go to System Preferences > Mail, and click "Reset" next to "Reset Mail". This will reset all Apple Mail settings to their default values.

If none of these steps resolve the issue, you may want to reach out to Apple Support or a professional for further assistance.