Microsoft 365 Calendar Won't Sync with iPhone or Webmail

Hello Berry,

Welcome to Microsoft Community. I am a Microsoft user just like you, I hope you are doing well.

I'm sorry to hear that your MS 365 calendar is not syncing with your iPhone and Webmail. This can happen if there is a problem with the Exchange ActiveSync protocol, which is used to sync your calendar and other data across your devices. There are some possible solutions that you can try to fix this issue:

• Check your internet connection and make sure it is stable and fast. Sometimes, a poor or intermittent connection can cause syncing issues.

• Check your date and time settings and make sure they are correct and consistent on your laptop, iPhone, and Webmail. Sometimes, a mismatch in the date and time can cause syncing issues.

• Check your MS 365 account settings and make sure you have enabled calendar syncing for your account. To do this, go to the Outlook app on your laptop and click on File > Account Settings > Account Settings. Select your MS 365 account and click on Change. Click on More Settings and then on the Advanced tab. Make sure the Use Cached Exchange Mode option is checked and the Download shared folders option is unchecked. Click on OK and then on Next. Click on Finish and then on Close.

• Check your iPhone settings and make sure you have added your MS 365 account as an Exchange account and enabled calendar syncing for it. To do this, go to Settings > Passwords & Accounts and tap on Add Account. Tap on Exchange and enter your MS 365 email address and password. Tap on Next and then on Sign In. Tap on Save and then on your MS 365 account. Make sure the Calendars option is turned on. Tap on Done.

• Check your Webmail settings and make sure you have enabled calendar syncing for your MS 365 account. To do this, go to outlook.office.com and sign in with your MS 365 email address and password. Click on the Settings icon and then on View all Outlook settings. Click on Sync email and then on Other email accounts. Click on Add a connected account and enter your MS 365 email address and password. Click on OK and then on Save.

Thanks very much for your response.

Just to be clear, I'm using a Microsoft 365/Office subscription and not the APP.

I think the issue occurred with the latest MS 365/Office update.

Barry

Hi, I'm Diane and I'm happy to help you today.

I use Shaw/Rogers as my email provider.

Added to classic Outlook as an Exchange Active Sync account, correct?

The bug was fixed in fixed in Outlook Desktop Version 2402 Build 17328.20068 and higher. You have higher version, so it should be working.

If you follow the instructions in this article to revert to the older build, does two-way syn c work again? https://support.microsoft.com/office/outlook-desktop-exchange-activesync-connections-stopped-working-in-version-2401-da2dc0dd-297e-48ba-b6d9-ab18f5d522fc

Let me know how it goes, I'm here to help you further if needed.

-- Diane

Hi Diane,

Thank you so much for your reply. Much appreciated.

I may need some assistance from a technical support to revert back to that particular version. Will let you know.

Have a good evening.

Barry

Follow the steps in that article - I have screenshots in this article - https://www.slipstick.com/outlook/uninstall-update-office-click-run/ - but my samples are for a different version. You need to use the command line in the Microsoft article- I use one command line in my article because I think its easier for people unfamiliar with the command prompt.

"C:\Program Files\Common Files\microsoft shared\ClickToRun\officec2rclient.exe" /update user updatetoversion=16.0.17126.20132

Disclaimer: slipstick.com is a site I run as a Microsoft MVP and the content is much more accurate and relevant than a general internet search. While the site is in English, there are translations options under the search box.