How to repair synchronisation Outlook New on PC with icloud calendar

Question

How to repair synchronisation Outlook New on PC with icloud calendar

Ivo Wallimann-Helmer 20

Hi,

since some day my outlook new on my PC does not update my icloud calendar entries I do on my iphone with apple calendar. Entries are synchronised only within my machines using either outlook or icalendar.

Deleting and reinstalling the account did not help.

Best and thanks

[moderator's note: PII removed]

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Answer accepted by question author

Vikki-T 13,230 Microsoft External Staff Moderator

Hi Ivo Wallimann-Helmer,

I understand how inconvenient it is when calendar entries created on your iPhone no longer appear in new Outlook, especially after you have already removed and added the account again.

Before changing the Outlook setup further, please open one of the affected events on your iPhone and check which calendar it was saved to. It should be stored under your iCloud calendar rather than On My iPhone or another account.

Please then sign in to iCloud.com and check whether the same event appears in Calendar there:

If it is missing from iCloud.com, the event is not reaching iCloud from the iPhone, so the issue is on the Apple Calendar/iCloud side.
If it appears on iCloud.com but remains missing from new Outlook, please open Settings > Accounts > Your accounts in new Outlook, select Manage beside the iCloud account, and check whether the account was connected through the Apple sign-in and permission page.

It would also help to know whether events created in new Outlook appear on the iPhone. This will show whether synchronization has stopped in only one direction or in both directions.

Please note that Apple Calendar and iCloud are third-party services. Microsoft does not control their synchronization settings or service availability. Thank you so much for your understanding.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Ivo Wallimann-Helmer 20 Reputation points

2026-10-21T12:41:42.2833333+00:00

Many thanks. Did all not help...
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-22T09:13:06.78+00:00

Hi Ivo Wallimann-Helmer,

Thank you for the update. I’m sorry that none of the previous suggestions resolved the issue.

Could you please confirm whether the affected event is visible in Calendar on iCloud.com but still missing from new Outlook? This one detail will help determine whether the issue is between the iPhone and iCloud or specifically between iCloud and new Outlook.
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-23T09:13:55.8566667+00:00

Hi Ivo Wallimann-Helmer,

If you still have further concerns, please feel free to let me know.
Will 0 Reputation points

2026-10-28T12:33:10.1133333+00:00

Hi Vikki-T,

I'm experiencing a very similar issue with iCloud Calendar syncing in New Outlook for Windows. Everything was working fine until recently, but newly created events are no longer syncing.

I've performed the following tests:

iCloud → Outlook: I created a test event in my iCloud Calendar on my iPhone. It appeared correctly on iCloud.com and my other Apple devices, but not in New Outlook.

Outlook → iCloud: I created another test event directly in my iCloud Calendar within New Outlook. The event appeared in Outlook, but not on iCloud.com or any of my Apple devices.

Removing and re-adding the account: I removed my iCloud account from New Outlook and added it again using Apple's sign-in process. Unfortunately, this made no difference. Outlook still displays the previously synced calendar events, but none of the newer events appear.

My iCloud Mail continues to sync normally in New Outlook, and I've confirmed that Microsoft's access to my Apple Account is still authorised.

Based on these tests, it seems that calendar synchronisation has stopped working in both directions, while email synchronisation remains unaffected.

I hope these additional details help narrow down the issue. Could this be a problem with the iCloud Calendar integration in New Outlook, rather than an account configuration issue?

I'd appreciate any further troubleshooting suggestions or confirmation of whether this is a known issue.

Thank you!
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-29T11:01:05.3133333+00:00

Hi Will,

Thank you for sharing the detailed test results. Since the iPhone event reaches iCloud.com successfully, but new events do not synchronize between iCloud and new Outlook in either direction, this does not appear to be an issue with selecting the wrong calendar on the iPhone.

The fact that iCloud Mail continues to sync and the account remains authorized also suggests that the account itself is still connected, while calendar synchronization is the affected part. However, I cannot confirm from the forum whether this is a currently recognized service issue or examine the synchronization logs.

As you have already removed and re-added the account through Apple’s authorization process, I would not recommend repeating that step. Please report the issue from new Outlook through Help > Feedback and include the two synchronization tests you described, along with your new Outlook and Windows versions. This will allow the Outlook team to receive the relevant diagnostic information and investigate the calendar integration.

Thank you again for documenting the behavior so clearly.
Will 0 Reputation points

2026-10-29T11:50:48.5066667+00:00

Hi Vikki-T,

I just submitted the feedback through New Outlook, including the reproduction steps and version information. Thank you for your assistance.
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-29T13:31:16.4733333+00:00

Hi Will,

Thank you for the update and for taking the time to submit the feedback with the reproduction steps and version information. Those details provide useful context for the Outlook team to review the calendar synchronization issue.

I appreciate your cooperation and the thorough testing you shared with the community.

1 additional answer

Your answer

Ivo Wallimann-Helmer 20 Reputation points

2026-10-21T12:41:42.2833333+00:00

Many thanks. Did all not help...
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-22T09:13:06.78+00:00

Hi Ivo Wallimann-Helmer,

Thank you for the update. I’m sorry that none of the previous suggestions resolved the issue.

Could you please confirm whether the affected event is visible in Calendar on iCloud.com but still missing from new Outlook? This one detail will help determine whether the issue is between the iPhone and iCloud or specifically between iCloud and new Outlook.
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-23T09:13:55.8566667+00:00

Hi Ivo Wallimann-Helmer,

If you still have further concerns, please feel free to let me know.
Will 0 Reputation points

2026-10-28T12:33:10.1133333+00:00

Hi Vikki-T,

I'm experiencing a very similar issue with iCloud Calendar syncing in New Outlook for Windows. Everything was working fine until recently, but newly created events are no longer syncing.

I've performed the following tests:

iCloud → Outlook: I created a test event in my iCloud Calendar on my iPhone. It appeared correctly on iCloud.com and my other Apple devices, but not in New Outlook.

Outlook → iCloud: I created another test event directly in my iCloud Calendar within New Outlook. The event appeared in Outlook, but not on iCloud.com or any of my Apple devices.

Removing and re-adding the account: I removed my iCloud account from New Outlook and added it again using Apple's sign-in process. Unfortunately, this made no difference. Outlook still displays the previously synced calendar events, but none of the newer events appear.

My iCloud Mail continues to sync normally in New Outlook, and I've confirmed that Microsoft's access to my Apple Account is still authorised.

Based on these tests, it seems that calendar synchronisation has stopped working in both directions, while email synchronisation remains unaffected.

I hope these additional details help narrow down the issue. Could this be a problem with the iCloud Calendar integration in New Outlook, rather than an account configuration issue?

I'd appreciate any further troubleshooting suggestions or confirmation of whether this is a known issue.

Thank you!
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-29T11:01:05.3133333+00:00

Hi Will,

Thank you for sharing the detailed test results. Since the iPhone event reaches iCloud.com successfully, but new events do not synchronize between iCloud and new Outlook in either direction, this does not appear to be an issue with selecting the wrong calendar on the iPhone.

The fact that iCloud Mail continues to sync and the account remains authorized also suggests that the account itself is still connected, while calendar synchronization is the affected part. However, I cannot confirm from the forum whether this is a currently recognized service issue or examine the synchronization logs.

As you have already removed and re-added the account through Apple’s authorization process, I would not recommend repeating that step. Please report the issue from new Outlook through Help > Feedback and include the two synchronization tests you described, along with your new Outlook and Windows versions. This will allow the Outlook team to receive the relevant diagnostic information and investigate the calendar integration.

Thank you again for documenting the behavior so clearly.
Will 0 Reputation points

2026-10-29T11:50:48.5066667+00:00

Hi Vikki-T,

I just submitted the feedback through New Outlook, including the reproduction steps and version information. Thank you for your assistance.
Vikki-T 13,230 Reputation points Microsoft External Staff Moderator

2026-10-29T13:31:16.4733333+00:00

Hi Will,

Thank you for the update and for taking the time to submit the feedback with the reproduction steps and version information. Those details provide useful context for the Outlook team to review the calendar synchronization issue.

I appreciate your cooperation and the thorough testing you shared with the community.

Answer 1

First check whether the iPhone event reaches iCloud.com; if it appears there and in classic Outlook but not in New Outlook, use classic Outlook as the practical workaround and report the New Outlook-specific synchronization failure.

1. Identify where synchronization stops

Create a uniquely named test appointment in Apple Calendar on the iPhone, ensuring it is saved under an iCloud calendar rather than an Outlook or local calendar.

Sign in to iCloud.com and open Calendar.
Look for the test appointment:
- Missing from iCloud.com: the problem is between the iPhone and iCloud. Follow Apple’s iCloud Calendar synchronization checks, including confirming the selected calendar and iCloud Calendar settings ^1^.
- Present on iCloud.com: the iPhone-to-iCloud stage is working; continue below.
If classic Outlook is installed, open it and inspect the iCloud calendar:
- Present in classic Outlook but absent from New Outlook: this isolates the failure to New Outlook.
- Absent from both Outlook clients: troubleshoot the Windows iCloud integration.

2. If only New Outlook fails

Microsoft now documents adding an iCloud account directly to New Outlook through Apple’s browser authorization:

In New Outlook, select View → View settings or File → Account info.
Open Accounts → Your accounts.
Select Manage beside the iCloud account and determine whether the account was previously connected through the Apple browser authorization flow.

Since deleting and reinstalling the account already made no difference, do not repeat it unless the previous setup did not open an Apple sign-in page and request permission. In that specific case:

Remove the iCloud account under Accounts → Your accounts → Manage → Remove.
Select Add Account and enter the iCloud address.
On Sync your iCloud account, select Continue.
Complete the Apple browser sign-in and select Allow on the permissions page.
Wait for Success, reopen New Outlook, and check the test event.

This is Microsoft’s current OAuth-based iCloud account connection procedure ^2^. OAuth 2.0 support for iCloud accounts was added to New Outlook on October 3, 2025 ^3^. However, the account-setup documentation does not establish that reconnecting repairs this particular calendar-sync failure.

If the event still appears on iCloud.com and in classic Outlook but not in New Outlook, continue using classic Outlook for the iCloud calendar. Similar New Outlook-specific iCloud calendar behavior has been reported in Microsoft’s community ^4^.

3. If neither Outlook client receives the event

Configure the documented classic Outlook integration through iCloud for Windows:

Open iCloud for Windows and sign in.
Enable Contacts and Calendars.
Select Apply.
Open classic Outlook and check the iCloud calendar.

Microsoft documents this integration for Outlook for Microsoft 365, Outlook 2024, 2021, 2019, and 2016—not New Outlook ^5^.

If it is already enabled, use Apple’s next reset step: sign out of iCloud for Windows, sign back in, and re-enable calendar synchronization ^1^. This is different from reinstalling the Outlook account.

Do not run classic Outlook profile or calendar troubleshooters against New Outlook; Microsoft states that classic Outlook troubleshooters are not applicable to New Outlook ^6^.

4. Report the client-specific failure

If New Outlook alone fails, submit feedback/support from New Outlook and include:

New Outlook version/build
Windows version
iCloud for Windows version, if installed
Whether the event appears on iCloud.com
Whether it appears in classic Outlook
Whether the account was authorized through the Apple browser permission page
Approximate event creation time and synchronization delay
Screenshots with personal information hidden

Also report it to Apple Support if the event fails in both Outlook clients after the documented iCloud for Windows setup.

References