synch outlook calendar

Hi L Watters,

Thank you for posting to Microsoft Q&A. I understand how disruptive it can be when your calendar doesn’t stay in sync, and I truly appreciate you taking the time to troubleshoot.

Please try the steps below, which typically help restore Outlook calendar syncing with an iPhone:

• Confirm calendar sync is enabled On your iPhone, go to Settings > Mail > Accounts > Outlook and ensure Calendars is turned ON.
• Refresh the sync connection Turn Calendars OFF, wait a few seconds, then turn it back ON.
• Restart your devices Restart both your iPhone and Outlook on your laptop to clear any temporary sync issues.
• Re-add the account (if needed) If the issue continues, remove your Outlook account from the iPhone and add it again.

Important note Calendar syncing requires the account to be set up as an Exchange/Outlook account. IMAP or POP accounts do not support calendar sync.

If you’ve already tried all of the above and the issue started recently, this may be related to a temporary Outlook service degradation that has impacted some iOS users. In that case, I would recommend waiting for the next service update.

I’m sorry for the inconvenience this has caused and thank you very much for your patience. Please don’t hesitate to reach out if you need further assistance.

If the answer was helpful, please click on "Accept Answer" and vote positive. If you have any additional questions, you can click on "Comment".

Note: Please follow the steps in our documentation to enable email notifications if you want to receive alerts about this thread.

Use these steps to restore calendar sync between the Outlook calendar on the laptop and the iPhone.

1. Verify the account is cloud-based and added on both devices

• Ensure the same email account is configured in Outlook on the laptop and on the iPhone (either in the Outlook mobile app or in the iPhone Calendar app via an Outlook/Exchange/Outlook.com account).
• On iPhone, to use the built-in Calendar app with Outlook:
  1. Open Settings.
  2. Scroll to and tap Calendar.
  3. Tap Calendar Accounts.
  4. Either select the existing Outlook/Exchange/Outlook.com account or tap Add Account and choose Outlook.com, then sign in.
  5. After adding, open that account and ensure Calendar is turned on.
  6. Open the Calendar app, tap Calendars, and confirm the Outlook calendar is selected.

2. If using the Outlook mobile app on iPhone

• In the Outlook app:
  1. Go to Settings.
  2. Tap the account that is not syncing.
  3. Tap Reset Account and wait for resync.
• If still not syncing:
  1. From Settings, tap the same account.
  2. Tap Delete Account > Delete From This Device.
  3. Re-add the account in Outlook for iOS and ensure Calendar is enabled for that account.

3. Confirm the account type supports calendar sync

• If the account is set up as IMAP in Outlook for iOS, calendar and contacts will not sync.
• If prompted to set up as IMAP, instead configure it as Exchange/Outlook.com or the provider’s native Exchange ActiveSync option.

4. Verify sync from the PC side

• Set up or confirm the email account in Outlook on the laptop using the Exchange protocol (not POP/IMAP) so calendar items are stored in the mailbox.
• Create a test event in the Outlook calendar on the laptop.
• Close Outlook, restart the PC, reopen Outlook, and confirm the test event appears.
• Then check the iPhone (Outlook app or Calendar app) to see if the test event appears.

5. If events still do not appear on iPhone

• In the Outlook mobile app:
  1. Go to Calendar.
  2. Tap the three lines (menu) in the upper left.
  3. Under the email account, ensure Calendar is checked.
• On iPhone (for Outlook app contacts/calendar access):
  1. Open Settings > Outlook.
  2. Ensure Background App Refresh is on.

These steps re-establish a proper Exchange/Outlook connection and force a fresh resync of the calendar between the laptop and iPhone.

References:

• Can't sync calendar and contacts with my phone or tablet
• Connect Outlook and Apple iPhone calendars