How to open other user folder in the new outlook?

Dear @Malak, Samer,

Thank you for posting your question in the Microsoft Q&A forum.

Before giving you the best solution, could you please confirm these questions below to help me diagnose the issue more effectively: 

• Does your account use a personal account (@outlook.com/@hotmail.com email), or is it a work/school account (e.g., @company.com)? 
• What kind of file or folder are you trying to access? Is it a shared mailbox, calendar, OneDrive file, PST archive, or something else?
• How is the file shared with you? Did the other user send you a sharing link, delegate access, or add you to a shared folder?
• What happens when you try to open it in the new Outlook?
• Do you get an error message? If possible, please kindly share the screenshot to me for better assist

According to my research, users can access other users' files or folders directly from the new Outlook without switching back to the classic Outlook.

• For more detail instructions, visit: Share and access another person's mailbox or folder in Outlook
• Requirements: The other user has shared the folder or mailbox with you, and You’ve accepted the sharing invitation, which will then make the folder appear in your folder pane.

Once shared, the folder should appear automatically if permissions are correctly set. If not, you may need to manually add it via: Right-click your name in the folder list > Select Add shared folder > Enter the email address of the user who shared it > Click Add

• Note: PST files (Outlook Data Files) are not fully supported in the new Outlook unless you're using a Microsoft 365 subscription and have classic Outlook installed. Even then, access is read-only for now. For reference: Using pst files in Outlook using when trying the "new Outlook.

Manage Folders:

In new Outlook you can view all mailboxes and folders shared with you, including details for the type of permissions you were granted. For more detailed information: View, hide, or remove shared mailboxes or shared folders in Outlook

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.

Thank you for your patience and your understanding. If you have any questions, please feel free to reach out.

I'm looking forward for your reply.

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