New Outlook: Calendar view cannot open modal dialogs (e.g. new event/settings) – Mail view works

I've been troubleshooting the above new issue (to me) with Copilot to produce the below summary. Hope this is helpful and you can advise and/or resolve ASAP!

Thanks.

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We are experiencing a consistent issue in New Outlook for Windows, with similar reports from Outlook for Mac, where Calendar view fails to display modal dialogs.

This affects:

• Creating new calendar events
• Editing or duplicating events
• Opening Settings

When triggered from Calendar view, no dialog appears and the UI becomes unresponsive for that action.

Note: Once calendar view 'breaks' Outlook, even switching back to mail view doesn't always work (incl. inability to close via usual X top right).

Key behaviour

• ✅ Issue occurs only in Calendar view
• ✅ Same functionality works correctly from Mail view:
  • New → Event opens and works
  • Settings opens normally
• ✅ Outlook Web (PWA) and Teams Calendar work without issue
• ✅ Switching from Calendar → Mail immediately restores functionality

Impact

• Users cannot effectively manage calendars using the desktop app (only view)
• Disrupts scheduling workflows
• Requires switching views or using other apps to complete basic actions

Scope

• Multiple users affected
• Reproduced across:
  • Windows (New Outlook)
  • Mac (similar behaviour reported)
• Not device-specific
• Not account-specific

Troubleshooting already attempted

• App repair/reset
• Full reinstall
• Restarting WebView2 processes
• Clearing local app data

No resolution (only temporary, same as killing task and restarting app).

Observed pattern

This appears to be isolated to the Calendar view UI layer, specifically:

• Modal/dialog rendering fails only when invoked from the Calendar canvas
• The same dialogs work when invoked from Mail context

Suspected cause

Likely a regression in the Calendar canvas/modal framework in New Outlook (Monarch) affecting dialog rendering.

This is consistent with previously observed Calendar-specific rendering issues in New Outlook (UI-layer defects limited to Calendar view rather than Exchange Online service).

Request

• Confirm whether this is a known or emerging issue
• Provide workaround or mitigation guidance
• Advise if this is linked to a recent feature rollout / flighting
• Share ETA for fix if available

Workaround (confirmed)

• Use Mail view → New → Event
• Use Outlook Web (PWA) or Teams Calendar

Additional notes (optional)

• Issue appears tied to Calendar view state rather than service/backend
• Switching views consistently resets behaviour (albeit not consistently/long term)
• Suggest investigating Calendar modal rendering lifecycle