How to use created tags in a shared mailbox in Microsoft Outlook?

Hello @Eliza,  

Thank you for reaching out to the Q&A forum! 

I noticed that your title mentions a shared mailbox, but in your description, you refer to your CEO’s main mailbox where you were granted Owner permissions.  

Could you please confirm if this is indeed the CEO’s primary mailbox and not a separate shared mailbox? 

Additionally, to support you better, please provide me more detail: 

1. Could you let me know how the permissions were granted?
2. If possible, could you share a screenshot of this issue?

Note: I will help you blur or hide any personal information if needed.      

The reason I’m asking is that I tested a similar scenario by granting Full Access through the Admin Center (Read and manage permissions), and in my environment I was still able to use tags in Outlook on the web.

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Hello @Eliza,  

Thank you for responding.

From what I see, you currently have Owner permissions for the Inbox folder only, not for the entire mailbox. This could be the reason why the Categorize (Tags) option remains grayed out in Outlook on the web. 

At the moment, I don’t have a test environment available to confirm this behavior, but if needed, I can run a test later and share the results.  

Based on your question and my initial testing, if you’d like to use tags in the CEO’s mailbox, you’ll need Full Access to the entire mailbox. 

You can ask your CEO (or your organization’s admin) to grant you Full Access by: 

Note: If you and your CEO are an end user, please contact your IT administrator to perform these steps.   

• Going to Microsoft 365 Admin Center=> Users => select the CEO’s account. 
• Under Mail settings, please open Mailbox permissions. 
• In Read and manage permissions, click Add permissions and select your account and save changes. 

About your side, after that, you can wait a few minutes for permission to sync: 

• You sign in to Outlook on the web with your account and click your profile icon => Open another mailbox. 

• Enter the CEO’s email address. 
• Once the mailbox opens, check if the Categorize (Tags) option is still grayed out. 

Note: If the mailbox doesn’t open immediately or you see an error, you should wait a little longer and try again; it can take some time for changes to propagate. 

  Waiting for your reply!