You can set it up using Thunderbird if IMAP is enabled in your account settings on Office365 it just requires a few add-ons for everything to work correctly.
Download Required Extensions:
Lightning: https://www.mozilla.org/en-US/projects/calendar/
Ericsson Exchange 2007/2010/2013 Calendar, Tasks, Contacts and GAL Provider: https://github.com/Ericsson/exchangecalendar/releases
Restart Thunderbird
Configure Email Settings:
Configure IMAP
IMAP server: outlook.office365.com
IMAP port: 993
IMAP user: id@domain.com
IMAP security: SSL/TLS
Configure SMTP
SMTP server: smtp.office365.com
SMTP port: 587
SMTP user: id@domain.com
SMTP auth: Normalpassword
SMTP security: STARTTLS
Configure Office365 Global Address Book:
Open the address book and click “Add Exchange contact folder” in the menu bar
Enter the following configuration
Name: Office365 Contacts
Refresh: 3600
Add list to search: Checked
Use autodiscovery: Unchecked
Server URL: https://outlook.office365.com/EWS/Exchange.asmx
Primary email: id@domain.com
Username: id@domain.com
Domain: 'n/a'
Share Folder Id: 'blank'
Press the “Check server and mailbox” button, it should populate “Folder base: Contacts folder” and set the Path for you
Press Save
Configure Office365 Calendar/Tasks:
Open Thunderbird
File > New > Calendar
Select “On the Network”
Select “Microsoft Exchange 2007/2010/2013”
Set calendar display settings and attach it to the configured Office365 email account (usually eid@siue.edu)
Enter the following configuration:
Autodiscovery: Unchecked
Server URL: https://outlook.office365.com/EWS/Exchange.asmx
Primary email address: id@domain.com
Username: id@domain.com
Share Folder Id: 'blank'
Press the “Check server and mailbox” button, it should populate “Folder base: Calendar folder” and set the Path for you
Press Save
No; your contacts are shared over an entirely different protocol – Ramhound – 2014-08-23T00:21:55.517
IMAP doesn't synch contacts or calenders, IMAP synchs mail folders only. checking the FAQ's for postbox you appear to be out of luck. http://www.postbox-inc.com/faq#exchange
– Tyson – 2014-08-23T02:24:53.097