Mac Mail Stuck on “Downloading Messages” in macOS Tahoe 26? Fix

After updating to macOS Tahoe (26.), a lot of Mac users started noticing something odd with Apple Mail. The app just keeps saying "Downloading messages" sometimes for hours, sometimes for days. In some cases, people left their Mac on overnight, even plugged in, and it was still going the next day.

What makes it more confusing is that Mail still works. New emails come in, you can send messages, and nothing seems broken. Still, seeing that progress bar move back and forth all the time doesn’t seem right, and it makes users wonder what Mail is actually doing.

For most users, this behavior didn’t exist before Tahoe. The issue:

• The issue starts right after upgrading to macOS Tahoe
• The number of "downloading" messages keeps increasing
• Exchange and iCloud accounts seem to be involved more often than others
• _Reinstalling _macOS usually doesn’t help

Please try these fixes:

Change how often Mail checks for new messages

The first thing you should do when Mac Mail is stuck on “Downloading Messages” in macOS Tahoe 26 is to change how often Mail checks for new messages. Here’s how:

• Open Mail on your Mac
• Go to Mail > Settings > General
• Change Check for new messages from Automatically to Every 15 minutes (or 5 minutes)

For some users this reduced the constant activity. For others, it helped for a few days and then the problem came back.

Toggle iCloud Mail syncing

If you use iCloud Mail, this may fix the problem.

• Go to System Settings
• Click Internet Accounts
• Select iCloud
• Click Mail
• Turn Sync this Mac off
• Wait a moment, then turn it back on

Remove and re-add Exchange accounts

• Open Mail > Settings > Accounts
• Remove the Exchange mail account
• Quit and reopen Mail
• Add the account back and test

Please note that this can be time consuming, and for some users the issue returned later, which is not good.

Safe Mode

Some users say that booting into Safe Mode, logging in, then restarting normally. This rebuilds caches. Sometimes that alone is enough to stop Mail from looping in the background. Here is how:

On Apple silicon Macs (M1, M2, M3, M, M5):

1. Shut down your Mac
2. Press and hold the Power button
3. When you see Loading startup options, release the button
4. Select your startup disk, usually Macintosh HD
5. Hold Shift, then click Continue in Safe Mode
6. Log in when prompted (you may have to log in twice)

On Intel Macs:

1. Shut down your Mac
2. Turn it on and immediately hold the Shift key
3. Release Shift when you see the login window
4. Log in