Apple Mail Not Working on Mac

Applies to: Mail app on macOS (Ventura, Sonoma, Sequoia and later)

1. Force-quit and reopen Mail

1. Press Cmd+Option+Esc, select Mail, click Force Quit.
2. Reopen Mail and give it a minute to reconnect before assuming it's still broken.

2. Check Internet Accounts

1. Apple menu → System Settings → Internet Accounts (or Mail, Contacts, Calendars on older macOS).
2. Select your account and confirm Mail is toggled on.
3. Toggle it off, wait a few seconds, then back on to force a refresh.

3. Rebuild the mailbox

This fixes most of what I'd call "stuck" mail — messages that won't load, appear duplicated, or just refuse to update.

1. Select the problem mailbox in the sidebar.
2. Menu bar → Mailbox → Rebuild.
3. Can take a while on a large mailbox — let it finish, don't force-quit partway through.

4. Check your internet connection and date/time

An incorrect system date/time causes secure mail connections to fail silently, with no obvious clue that's what happened.

1. System Settings → General → Date & Time → confirm "Set time and date automatically" is on.

5. Remove and re-add the account

1. System Settings → Internet Accounts → select account → click the minus button to remove it.
2. Restart Mail, then re-add it with the plus button.

6. Check for an old VPN configuration

If Mail throws a "Network Error (POSIX 61)" specifically, or started failing right after a macOS update, an old VPN profile you're not actively using can silently block Mail's connection. This is easy to miss since the VPN doesn't need to be connected to cause the problem — just configured.

1. System Settings → VPN → check for any profiles you don't actively use.
2. Remove them, or at minimum turn them off, then restart Mail.

7. Still crashing on launch?

Hold Shift while opening Mail to skip loading extra windows. If it keeps happening, Console.app usually has a crash log pointing at a specific corrupted plugin or plist file — worth a look before anything more drastic.

If nothing above has worked and the issue is specifically sync between devices rather than Mail crashing, deleting the Mail app itself (not just the account) and reinstalling it from the App Store has fixed persistent cross-device sync problems that toggling settings alone didn't — worth trying before assuming it's unfixable.