If you're running Mac OS 10.6 Snow Leopard or Mac OS 10.7 Lion, you can use the Mail program included with those releases to connect to your email account automatically using an Exchange account.
If you're running Mac OS 10.4 Tiger or Mac OS 10.5 Leopard, you can still use the Mac Mail App to connect to your account. However, you need to connect to your account without using IMAP or POP.
You can connect to Microsoft Office 365 using Mac Mail. Mac Mail provides both POP3 and IMAP4 capability. However, you won't get all the functionality available with full featured E-mail clients, such as Microsoft Outlook or Mac Mail with the Exchange interface.
Connecting using the Exchange account method requires fewer steps than using IMAP or POP. When you use Mac OS 10.6 Snow Leopard or Mac OS 10.7 Lion and connect using an Exchange account, you can use features that aren't available to users who connect through IMAP or POP, including iCal and Address Book. These programs help you manage your calendar and address book.
Help with Mac Mail 8.0 is available at the ITS Help Desk and the Open Access Labs.
Please note, all of the links below point to instructions on Microsoft's Web site. As updates are made to Office 365, these instructions will also be modified to show the most up to date information. The same is true if Thunderbird is upgraded. If you experience problems connecting your system to Office 365 using Thunderbird, you may want to check this site to see if changes are required in the setup for your computer.