Requesting help in re-adding iCloud to Office 365 Outlook Classic on my PC. (Not online Outlook)

Adding iCloud to Windows 365 Outlook Classic

I use Outlook Classic on my Windows 11 PC. I use iCloud to sync my calendar and contacts between my Windows PC and my iPhone 15Pro. All was working well and then it wasn't.


I followed the tip - uninstall iCloud for Windows from MS Outlook.


I can see calendar and contacts on iCloud but I cannot get to sync with Outlook Classic on my PC.


Tips are welcome! Thanks!!

Windows, Windows 11 (26200)

Posted on Nov 19, 2025 3:30 PM

Reply
Question marked as Top-ranking reply

Posted on Dec 9, 2025 10:40 PM

To restore iCloud → Outlook Classic sync:

  1. Ensure Outlook is Classic, not “New Outlook.”
  2. Uninstall iCloud completely.
  3. Repair Microsoft Office.
  4. Reinstall Apple’s version of iCloud for Windows.
  5. Re-enable the iCloud Outlook Add-in.
  6. Make sure the iCloud .ost file appears in Outlook.
  7. Delete corrupted iCloud cache files if needed.


Once done, your Contacts + Calendar will reappear in Outlook and sync bi-directionally again.

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3 replies
Question marked as Top-ranking reply

Dec 9, 2025 10:40 PM in response to MikeLostWithiCloud

To restore iCloud → Outlook Classic sync:

  1. Ensure Outlook is Classic, not “New Outlook.”
  2. Uninstall iCloud completely.
  3. Repair Microsoft Office.
  4. Reinstall Apple’s version of iCloud for Windows.
  5. Re-enable the iCloud Outlook Add-in.
  6. Make sure the iCloud .ost file appears in Outlook.
  7. Delete corrupted iCloud cache files if needed.


Once done, your Contacts + Calendar will reappear in Outlook and sync bi-directionally again.

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Requesting help in re-adding iCloud to Office 365 Outlook Classic on my PC. (Not online Outlook)

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