Estimated Time to Fix: 5 minutes

Summary

When your company enables Multi-Factor Authentication (MFA), it changes how applications are allowed to sign in. The default Apple Mail app on your Mac often gets confused during this transition. Instead of showing you the new Microsoft or Google sign-in window to approve the MFA prompt, it endlessly rejects your password. Here is how to force Apple Mail to recognize the new security settings.

Before You Start

• You must know your current work email address and password.
• You need your phone nearby to approve the MFA prompt.

Instructions

1. Delete the Stale Account

The fastest and most reliable way to fix this is to remove the email account from your Mac and add it back. This forces Apple Mail to download the newest security settings. Do not worry; this will not delete your actual emails. Your emails live safely in the cloud.

1. Click the Apple menu — the apple in the top-left corner of the screen.
2. Select System Settings (or System Preferences on older Macs).
3. Scroll down the left sidebar and click Internet Accounts.
4. Click on your work email account in the list (usually labeled "Exchange" or "Google").
5. Click the Delete Account button at the bottom.
6. Confirm that you want to delete it.

2. Re-Add the Account Properly

Now you need to add it back so the modern authentication window triggers.

1. Still in the Internet Accounts menu, click Add Account.
2. Select the correct service:
   • Choose Microsoft Exchange if your company uses Microsoft 365/Outlook.
   • Choose Google if your company uses Google Workspace/Gmail.
3. Type in your name and your work email address, then click Sign In.
4. Crucial Step: A popup will ask if you want to "Sign in to your Exchange account using Microsoft" (or Google). You must click Sign In. Do not click "Configure Manually".
5. A web browser window will pop up. Enter your password here.
6. Approve the MFA prompt on your phone (text message or authenticator app).

3. Sync Your Mail

Once authenticated, Apple will ask what apps you want to sync.

1. Ensure the toggle for Mail is turned on.
2. You can also optionally turn on Contacts, Calendars, and Reminders.
3. Click Done.
4. Open the Apple Mail app. It will say "Downloading Messages" at the bottom left. Give it a few minutes to pull down your inbox.

If the password box comes back after you have re-added the account, the block is on the account rather than on your Mac, and no amount of retyping the password clears it. Raise a ticket giving your macOS version from Apple menu > About This Mac, the exact wording of the sign-in message, and the fact that deleting and re-adding the account did not trigger the MFA prompt on your phone.

Troubleshooting

WARNING

If your Mac is very old (running macOS 10.13 High Sierra or older), Apple Mail physically does not support modern MFA. You will be forced to use the Outlook App or access your email through a web browser instead.

Symptom / Error	Potential Cause	Solution
"Unable to verify account name or password"	Wrong service selected	Make sure you selected "Microsoft Exchange" and not the generic "Mail account" option when adding it back.
My subfolders are empty	Sync in progress	Apple Mail downloads the main Inbox first, then works on subfolders in the background. Leave the app open and connected to Wi-Fi for 30 minutes to finish syncing.

Related Articles

• How to Tell if Your Microsoft 365 Account is Signed In Correctly

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