Estimated Time to Fix: 5 minutes

Summary

Fix Outlook email, calendar, or contacts not syncing on your iPhone or Android phone. This guide covers connection checks, app restarts, sync settings, account resets, and re-adding your account.

Symptoms

• New emails don't appear on your phone, but they show up on your computer or in Outlook on the web.
• Calendar events are missing or show the wrong time.
• Contacts added on your computer don't appear on your phone.
• Outlook shows "Syncing..." indefinitely or displays a sync error banner.
• Sent emails from your phone don't appear in Sent Items on other devices.

Before You Start

• The Outlook mobile app (iOS or Android).
• Your Microsoft 365 work email account.
• An active internet connection (Wi-Fi or mobile data).

Instructions

1. Check Your Internet Connection

Outlook needs an active internet connection to sync.

1. Open your phone's web browser and load any website to confirm you have internet.
2. If you're on Wi-Fi and it's not working, switch to mobile data (or vice versa) to test.
3. If you have no internet at all, fix your connection first and return to this guide. If web pages load normally and Outlook still shows nothing new, your connection is not the cause. Continue to Step 2.

2. Force Close and Reopen Outlook

A quick restart of the app often resolves temporary sync issues.

1. iPhone: Swipe up from the bottom (or double-press the Home button) to open the app switcher. Swipe the Outlook card up to close it.
2. Android: Tap the Recent Apps button (square icon), find Outlook, and swipe it away.
3. Wait 5 seconds, then reopen the Outlook app.
4. Check if your emails and calendar have updated. If the newest message in your inbox is still the one you saw before the restart, a stuck app session was not the cause. Continue to Step 3.

3. Check Outlook Sync Settings

Make sure Outlook is set to sync all your data.

1. Open the Outlook app and tap your profile picture (or the account icon) in the top-left corner.
2. Tap the gear icon (⚙️) to open Settings.
3. Tap your email account under Mail Accounts.
4. Verify that Sync Calendar and Sync Contacts are both turned On.
5. Check that sync email range is set to Last 1 Month or All (shorter ranges may hide recent messages). If every toggle was already set to On and the range already covers recent mail, your settings are not what is holding the sync back. Continue to Step 4.

4. Reset the Account

Refresh the account connection without deleting it.

1. Open Outlook, go to Settings, and tap your email account.
2. Scroll down and tap Reset Account.
3. Confirm the reset.

Outlook re-syncs all your data from the server. This can take a few minutes depending on your mailbox size.

TIP

An account reset is the fastest fix for most sync problems. It forces Outlook to re-establish the connection to the server without losing your settings or drafts.

If the reset finishes and your inbox still stops at the same old message, the local copy of the account is damaged rather than stale. Continue to Step 5.

5. Remove and Re-Add the Account

If resetting doesn't work, remove the account and add it back fresh.

1. Open Outlook, go to Settings, and tap your email account.
2. Scroll down and tap Delete Account.
3. Confirm the deletion.
4. Tap Add Account and sign in with your work email and password.
5. Complete MFA verification if prompted.
6. Wait for the initial sync to complete.

All your emails, calendar, and contacts re-download from the server — nothing is lost.

WARNING

After removing and re-adding the account, any draft emails stored only on your phone will be lost. Check your Drafts folder before deleting the account.

If the account finishes downloading and the newest emails are still missing, the block is on the account rather than the app. Raise a ticket saying which folders are out of date, the date and subject of the newest message that did arrive, and whether Outlook on the web shows the same gap on a computer.

6. Verify the Fix

Confirm everything is syncing correctly.

1. Check your inbox for recent emails.
2. Open the Calendar and verify upcoming meetings appear.
3. Send yourself a test email from another device and confirm it arrives on your phone within 1–2 minutes.

Troubleshooting

WARNING

If Outlook keeps losing sync after every fix, your organization may have a mobile device management (MDM) policy that's interfering. Check if Company Portal or Microsoft Intune shows any compliance issues on your device.

Symptom / Error	Potential Cause	Solution
"Account setup failed" when re-adding	MFA or conditional access block	Make sure you're completing the MFA prompt. If using a personal device, you may need to install Company Portal or Microsoft Authenticator first.
Calendar syncs but email doesn't	Email sync period too short	Go to Settings > your account and change the sync range to Last 1 Month or All.
Emails arrive on phone but not computer	Emails stuck in phone's outbox	Check the Outbox folder in Outlook mobile for unsent emails. Resend them.
Sync works on Wi-Fi but not on mobile data	Background data restricted for Outlook	Go to your phone's Settings > Apps > Outlook > Mobile data and enable Allow background data usage.
Notifications stopped along with sync	Battery optimization killing Outlook	Go to your phone's Settings > Battery > Outlook and select Unrestricted (or disable battery optimization for Outlook).
"Your IT admin has restricted access"	Device compliance issue	Open Company Portal and check for compliance warnings. See How to Fix "Device Not Compliant" Errors.

Related Articles

• How to Set Up the Outlook Mobile App
• How to Fix Outlook Emails Not Syncing (Desktop)
• How to Transfer MFA to a New Phone
• How to Fix "Device Not Compliant" Errors on Your Phone
• How to Change Your Microsoft 365 Password from Your Phone

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