GrinMark Synchronizer needs just one Office 365 account to connect to Exchange and synchronize data for user's mailboxes. This account does not even need an Office 365 license. The only requirement for the account is ApplicationImpersonation admin role.
Follow these simple steps to configure an Office 365 account for GrinMark Synchronizer.
Click Add a user button.

Enter user information and click Add button.

Note: Office 365 license is not necessary. So you may create new user without a product license.
Navigate to Exchange Admin Center.

In the permissions group click admin roles.

Click + button to configure Application Impersonation role.

Add gmsync user as a member of ApplicationImpersonation role. Click Save button.

Note: At least once login as a new user using Outlook Web interface. You may be prompted to change an auto-generate password.
Configuration is complete. You may now specify new user credentials in Exchange Connection settings in GrinMark Synchronizer.
