Outlook365 issue regarding Shared mailboxes

Hello Eleni

Thanks, will do that.

Regards

Jacco Dominicus

Hello Jacco Dominicus,

Thank you for your prompt response and for providing more details about the issues you're experiencing with shared mailboxes in the new Outlook.

Based on your feedback, I understand that:

• All users are experiencing the issues with shared mailboxes not syncing simultaneously and the Outbox not being visible.
• The "Sync shared mailboxes" option is not available in the new Outlook.
• There are no error messages displayed when trying to access the Outbox of the shared mailbox, as it's not visible.

Given this information, I recommend should be investigated futher by reaching out to your case to Microsoft support Microsoft support -Get support - Microsoft 365 admin | Microsoft Learn for further assistance. Please expect an email from the support team soon. Thank you.

Best regards,

Eleni | Microsoft Community Moderator

Hello Eleni,

Thanks for your reply

1. Are all users experiencing these issues, or only specific users? yes all users are experiencing the same
2. Have you tried configuring the shared mailbox settings to use the "Sync shared mailboxes" option? That option is not available in the new outlook
3. Are there any errors or messages displayed when trying to access the Outbox of the shared mailbox? The Outbox is not visable in the new outlook

Kind regards

Jacco Dominicus

Hello Jacco Dominicus,

Good day!

Thank you for reaching out to Microsoft Community with your issue regarding shared mailboxes in Outlook 365. I understand that you're experiencing two issues with the New Outlook which are shared mailboxes not syncing simultaneously among users and outbox of the shared mailbox not visible in the folder list.

To better understand and assist with your issue, can you please clarify the following:

1. Are all users experiencing these issues, or only specific users?
2. Have you tried configuring the shared mailbox settings to use the "Sync shared mailboxes" option?
3. Are there any errors or messages displayed when trying to access the Outbox of the shared mailbox?

The problem with attachments not forwarding in Outlook Classic is a known issue. The fact that switching to the new Outlook resolved this issue suggests that it was a limitation or bug in the Outlook Classic version. The new Outlook is designed to handle attachments more efficiently, and Microsoft recommends using the latest version for the best experience.

Shared Mailbox Synchronization

The shared mailbox not updating simultaneously for all users is a known issue.Microsoft has released fixes for similar issues in the past.

Here are some detailed steps to address this:

• Ensure that all users have the latest updates for Outlook installed.
• Instruct users to restart Outlook after switching from the classic to the new version to ensure a fresh session.
• If the problem persists, consider creating a new Outlook profile. This can be done by going to Control Panel > Mail > Show Profiles > Add. Follow the prompts to add a new profile and set it as the default.

Outbox Visibility

The Outbox not being visible in the folder list is also a recognized issue.One workaround is to check the Outlook web app (OWA) to confirm if the emails are indeed being sent. If they are, this could be a UI issue with the desktop client.If not, it might be related to permissions or mailbox storage capacity.

Here’s how to tackle this:

• Check if the Outbox is visible in the Outlook web app (OWA). If it is, the issue might be with the desktop client’s UI.
• If the Outbox is not visible in OWA, it could be a permissions issue. Ensure that all users have the appropriate permissions for the shared mailbox.
• To address the visibility issue in the desktop client, you can try adding the shared mailbox manually to each user’s Outlook profile. This can be done by going to File > Account Settings > Account Settings > New. Enter the shared mailbox’s email address and follow the prompts.
• If the synchronization issue continues, consider disabling “web caching” by unchecking “Download shared folders” under Account Settings > More Settings > Advanced. This will switch the shared mailbox to online mode, which may improve synchronization.
• For the Outbox issue, if manually adding the shared mailbox does not work, consider increasing the mailbox storage capacity if it’s near its limit, as this can sometimes cause issues with folder visibility.

Please try these detailed steps and let me know the results. f the problems persist, we may need to investigate further or reach out to Microsoft support -Get support - Microsoft 365 admin | Microsoft Learn for additional assistance. Thank you and have a great day.

Best regards,

Eleni | Microsoft Community Moderator