When certain events take place, Groove sends an email right to your inbox depending on your notification settings. Each user can choose their own notification preferences, based on how active they'd like to see Groove in their inbox. Admins do not have the ability to edit a user's notifications on their behalf, only the user can do it themselves.
To adjust your notifications, visit your Settings > My Settings > Notifications.
Enable the notifications you'd like to receive from Groove by checking (or un-checking) the boxes next to any of the notification options.
Click Save Notification Settings and you're all set! You'll receive an email from Groove next time any of the selected events takes place in Groove.
Read more on how you can update Groove conversations by replying to email notifications.
(Please note: there is no setting for @mention notifications and they cannot be disabled.)