How to recover Outlook calendar event data missing following Sequoia OS update on a MacBook Pro

Question

How to recover Outlook calendar event data missing following Sequoia OS update on a MacBook Pro

Dan Williams 20

Following recent Sequoia OS update, some calendar events in Outlook have data missing (e.g., mtg location, notes, status flags). The data is only missing on “series” type events, “single” calendar events were not affected. Is there a way to recover/find the Outlook data that existed before the OS update, or any other way to retrieve the missing data? Outlook is running on an MacBook Pro. The calendar in Outlook exist under the category “On My Computer”

‘There were no error messages following the OS update nor with running Outlook.

Any assistance or insights would be greatly appreciated, thanks!

Accepted answer

0 additional answers

Your answer

Answer 1

Winnie-B 780 Microsoft External Staff Moderator

Hello Dan,

Thank you for reaching out and welcome to Microsoft Q&A!

I'm sorry to hear about the missing data in your Outlook calendar. I understand it's frustrating and worrying when you lose important information, especially after an OS update.

Below are some steps that you could try:

1. Check if the missing data is truly gone or just not displaying

Open Outlook for Mac, go to Preferences → General → Turn off “New Outlook” (if you’re using New Outlook, switch back to Legacy Outlook). Some users report that recurring series data may not render correctly in the new interface. See if the details reappear in Legacy Outlook view.
Try expanding a recurring series into a single occurrence (open one instance and check “This Event Only”). Sometimes the details are still in the backend but not shown on the series container.

2. Check for local backup of the Calendar Database

Outlook for Mac stores local calendar data (especially “On My Computer” items) in a database. When macOS updates, sometimes this database can be affected. Here’s how to check for previous versions:

Close Outlook completely
Open Finder, then go to: ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/
Look for files like Outlook.sqlite or Calendar.sqlite.
Check if there are any backup copies, or use Time Machine, if enabled, to restore a version from before the OS update. (Note: If Time Machine is enabled on your Mac, this is the best chance to recover the lost data.)

3. Export what you still have

In Outlook, go to File → Export → choose Calendar → save as an .olm file.
This ensures you have a backup of the current calendar before you attempt recovery steps, so nothing gets overwritten.

4. Try creating a new Outlook profile

Quit Outlook, then open Outlook Profile Manager (search Spotlight for “Outlook Profile Manager”).
Create a New Profile and re-add your account. If the calendar data is truly local, you may need to import the .olm backup into the new profile to check if the series data restores correctly.

I truly hope one of these methods helps you recover your calendar data. Please feel free to let me know how it goes. Take care!

Warm regards,

Winnie

PS: If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

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.

Dan Williams 20 Reputation points

2025-08-26T23:20:44.5533333+00:00

Winnie - great input, thanks. I have made a mistake; start switching to Legacy, I don’t want to do this, but it won’t let me back-out/exit or quite outlook. It won’t let me shut down th e MacBook either.

Help me get out so that I can implement your other suggestions.

It wants me to add my email account - which I have not used in outlook.
Winnie-B 780 Reputation points Microsoft External Staff Moderator

2025-08-27T11:29:12.9433333+00:00
Hi Dan,

Thank you for the update. I understand it's incredibly frustrating when an app freezes and prevents you from even shutting down your computer. The behavior you're describing is a software hang, where a process has become unresponsive and is locking up the application and your system. You can force the application to quit so you can regain control of your MacBook.

Here's what you could try:

Option 1: Force Quit Outlook

Press Command (⌘) + Option + Esc

In the “Force Quit Applications” window, select Outlook

Click Force Quit

This will completely close the Outlook process and let you return to the desktop.

Option 2: Use Activity Monitor (if Force Quit doesn’t work)

Open Spotlight Search (press Command + Space)

Type Activity Monitor and press Enter

In the list of processes, find Microsoft Outlook

Click to select it, then click the “X” icon at the top left to force it to quit

After successfully force-quitting the app, I recommend you restart your MacBook to clear any stuck processes.

I hope this helps you get out of the loop and back to resolving the main issue.

Warm regards,

Winnie
Dan Williams 20 Reputation points

2025-08-27T18:37:42.06+00:00

Winnie - The Force Quite, opt 1, worked very well, and got me back where I wanted to be.

Please recognize that I greatly appreciate your assistance. Your input is specific, clear, directly focused on my issue, and very responsive/quick. Clearly the best tech support I’ve received over the years - many thanks!

Further update on the issue: Opening a “single event” in a calendar series did not reveal any missing data - tried several events at different points in time.

I did find an Outlook.sqlite file, it had an early August date; made a copy of it in a different folder and name.

I tried to export the calendar file from Outlook as you noted, unfortunately the pull down option to export and import files are grayed out and not functional; hence I cannot implement your steps 3 & 4 above.

I think I may have to simply accept not having the missing data; regardless, you have been extremely helpful and I’m smarter as a result.

If you have thoughts on the exporting issue, I welcome them.

I have not used Time Machine before, but I think I will going forward.

Sincere thanks!

Dan
Winnie-B 780 Reputation points Microsoft External Staff Moderator

2025-08-28T09:28:28.91+00:00
Hi Dan,

Thank you so much for your kind words, it truly means a lot to know the support has been helpful to you. I really appreciate the detailed update and all the steps you’ve taken so far.

About the “Export/Import” Option being grayed out

This typically happens when Outlook for Mac is in a restricted state, such as:

No active account is added

You’re still in the “New Outlook” interface, which doesn’t support exporting/importing .olm files

Or Outlook is experiencing a profile corruption or temporary glitch

Below are two safe options to get you to a place where you can export, then attempt recovery from your earlier database copy:

Option A (recommended): Switch to Legacy Outlook just long enough to export

1. Revert to Legacy Outlook

In Outlook, choose Outlook > Help > Revert to Legacy Outlook (or Outlook > New Outlook and turn the toggle off).

2. If Outlook shows an “Add Account” screen and won’t let you proceed:

Quit Outlook.

Hold the Option key and click the Outlook icon to open Outlook Profile Manager.

Select your existing Main Profile (the one that contains “On My Computer” data) and click Set as Default, then Open

3. In Legacy Outlook, enable local folders if they’re hidden:

Outlook > Preferences > General → uncheck “Hide On My Computer folders”.

4. Now try File > Export… → Calendar → export to an .olm file (choose “Items of these types” → Calendar; optionally set a date range up to the day before the macOS update).

If you can export, you’ll have a clean snapshot. You can then keep using New Outlook, and later File > Import… that .olm into a fresh profile to see if series details re-appear.

Option B (advanced, if A is blocked): Temporarily load your August database to export

Since you already located an Outlook.sqlite from early August:

1. Back up first

Quit Outlook.

In Finder, go to: ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/

Copy that entire Data folder to a safe location (external drive or Desktop).

2. Swap in the August copy (non-destructive test)

In the Data folder, rename current Outlook.sqlite to Outlook_current.sqlite.bak.

Place the August Outlook.sqlite in the same folder (rename it to exactly Outlook.sqlite).

3. Open Legacy Outlook (use the steps in Option A to ensure you’re in Legacy).

4. Try File > Export… > Calendar to an .olm.

5. Revert the swap

Quit Outlook.

Delete the test Outlook.sqlite and rename Outlook_current.sqlite.bak back to Outlook.sqlite.

6. Import the .olm you just created into your current profile to merge any recovered series details.

This gives you a one-time pull of the series metadata from August without losing newer events permanently.

If export remains greyed out

Double-check you truly are in Legacy Outlook (the “New Outlook” toggle should be off under Outlook > Preferences > General).

Ensure Hide On My Computer folders is unchecked.

Try View > Change View > List in Calendar, then File > Export….

If still blocked, you can drag events (or selected ranges) from Calendar to the Desktop to create .ics files as a fallback, then re-import them.

About Time Machine

So glad to hear you’re considering enabling Time Machine moving forward. For local (“On My Computer”) data, it’s the most reliable safety net after OS/app change.

Dan, thank you again for your patience and willingness to troubleshoot so thoroughly, I know this has been a time-consuming issue. And please feel free to reach out if you need further assistance, I’m here to help as much as I can.

Share via

How to recover Outlook calendar event data missing following Sequoia OS update on a MacBook Pro

0 additional answers

Your answer