Intuit Practice Management powered by Karbon integrates with the following email clients:
Gmail
Microsoft 365 Business Standard
Microsoft 365 Business Premium
Microsoft Exchange 2010 or newer
Further reading:
Note: On April 21, 2020, the names of the Microsoft plans changed:
Office 365 Business Essentials => Microsoft 365 Business Basic
Office 365 Business Premium => Microsoft 365 Business Standard
Microsoft 365 Business => Microsoft 365 Business Premium