To download your Office 365 mailbox to your local drive easily and safely, you can use the SysInfo Office 365 Backup Tool. This utility allows you to save all your emails, contacts, calendars, and attachments right onto your computer. It supports saving data in different formats like PST or PDF, so you can open your files with popular apps like Outlook or Adobe Reader. It also keeps your mailbox folders organized just like in Office 365.