Outlook - one or more objects in this for were not loaded.

WORKAROUND Since the native synchronization between iCloud and Outlook is currently unstable and prone to errors (such as the "folder doesn't support reminders" error or log failures), the most reliable solution right now is to bypass the iCloud sync engine entirely and use the Microsoft Exchange backend directly on the iPhone/Mac.

This is not a fix for the iCloud software bug, but a method to achieve the same result (tasks on iPhone, Mac, and PC) without errors.

The Steps:

On your iPhone, go to Settings > Reminders > Accounts. Ensure your Microsoft/Outlook account is added and the Reminders toggle is switched ON.

Go back to the main Settings > Reminders menu and tap on Default List.

Change the selection from your iCloud list to a list under your Microsoft/Outlook account (usually named "Tasks").

The Result: You can continue using the native Apple Reminders app, iOS Widgets, and Siri exactly as before. However, the data is now saved directly to the Microsoft server. This means your tasks will appear instantly in Microsoft To-Do and Outlook on your PC, completely avoiding the broken iCloud for Windows synchronization bridge. This also works perfectly on macOS by adding the Exchange account in System Settings.

Limitations: Please note that by moving your lists to Microsoft Exchange, you will lose the ability to share lists via the native Apple iCloud sharing method. To share lists, you must use the sharing features within Microsoft To-Do.

Fix for this issue is to use Word or Excel to define the ActiveX Security Level for all Office Programs (Outlook does not have this setting in the Trust Center)

File -> Options -> Trust Center -> [Trust Center Settings] -> ActiveX Settings

This is equivalent to the Registry Settings:
HKEY_CURRENT_USER\Software\Microsoft\Office\Common\Security
DisableAllActiveX = 0
UFIControls = 4

Also be sure that the iCloud Add-In is Enabled (checked):

File -> Options -> Add-Ins
Manage: COM Add-Ins [Go]

@Janet Holwell said

Please continue to try to resolve ["item is in a folder that doesn't support reminders"] problem

I have my iCloud/Outlook test rig set up.

Ran into the "prevent malicious code from running" bug and fixed it using the Answer from @Sergio Iglesias Borrego
https://learn.microsoft.com/en-us/answers/questions/5694531/(solved)-outlook-classic-icloud-(store-app)-malic

But I can NOT reproduce the "item is in a folder that doesn't support reminders" bug.

Mine creates meetings and appointments without a hitch.

Can you tell me anything about your setup that might be different that the bog standard environment I have? Shared Calendars? IMAP or POP email accounts? Is your primary Outlook calendar marked "This computer only"?

Hi @Janet Holwell

Thank you for reaching out to Microsoft Q&A.

Based on the information you shared, I understand that you are receiving the message “To prevent malicious code from running, one or more objects in this form were not loaded. For more information, contact your administrator” when opening Outlook calendar items, and that you are also unable to set reminders.

According to my research, Outlook reminders only work correctly when calendar items use the standard Outlook form. This issue commonly occurs if:

A custom form is being used for calendar items, or an add-in is interfering with calendar functionality or form loading.

To troubleshoot this issue, please try the following steps:

1. Run Outlook in Safe Mode Open Outlook in Safe Mode and check whether the issue still occurs.
2. Disable add-ins to isolate the cause If the issue does not occur in Safe Mode, go to Outlook > File > Options > Add-ins > Select COM Add-ins > Go… > Disable all add-ins and restart Outlook > Re-enable add-ins one by one, restarting Outlook each time, until the issue reappears > The last enabled add-in is likely the cause
3. Check the registry setting for ActiveX Navigate to: HKEY_CURRENT_USER\Software\Microsoft\Office\Common\Security\DisableAllActiveX > If the key exists, try changing its value to 0 and test again > Please make sure to back up the registry key before making any changes

I hope the above information is helpful. Please let me know your results or if you need further assistance.

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The message you are encountering in Outlook, stating that "one or more objects in this form were not loaded," typically indicates that Outlook is blocking certain content or objects within the calendar form to prevent malicious code from executing. This can happen due to security settings or policies enforced by your organization.

Additionally, the inability to set reminders could be related to the same security settings or possibly a Group Policy configuration that restricts certain features in Outlook. If reminders are being managed by Group Policy, you may not be able to modify these settings without contacting your domain administrator.

To troubleshoot this issue, you can try the following steps:

1. Check Group Policy Settings: If you are in a corporate environment, consult your IT administrator to ensure that the settings related to reminders and form loading are correctly configured.
2. Modify Outlook Options: If you have access, you can check your Outlook options to ensure that reminders are enabled. Go to File > Options > Advanced, and in the Reminders section, ensure that "Show reminders" is checked.
3. Repair Outlook: If the problem persists, consider repairing your Outlook installation through the Control Panel.
4. Update Outlook: Ensure that you have the latest updates installed for Outlook, as updates can fix bugs and improve functionality.

If these steps do not resolve the issue, further investigation may be needed, possibly involving your IT department for assistance with Group Policy settings.

References:

• Reminders in Outlook do not appear
• Outlook not responding error or Outlook freezes when you open a file or send mail