Overview:
The supported method for accessing your Dartmouth email on Linux is:
Outlook Web App (bwa.dartmouth.edu or outlook.dartmouth.edu)
Other options currently include:
Outlook Web App
To access your email through OWA, please visit http://bwa.dartmouth.edu in a current version of Firefox or Chrome. Other Linux web browsers may work but have not been tested.
Thunderbird
Mozilla Thunderbird does not have native support O365 mail however you can access it via the OWL for Exchange add-on that is available. This is a paid for (annual fee) add-on with a free trial.
More about the OWL add-on here.
Link to the add-on here.
There is currently a setup that is functional with the Evolution client. See the following KBA with setup steps here.