Strategy Distribution Services 9.x -10.x delivery notifications can only be sent to one user per Email transmitter. If the user enters a distribution Email list in the Email Transmitter Notification section as seen below, no error message will appear.
However, when users then send out subscriptions through Distribution Services, the delivery notification email will not be received by the users in the distribution email list.
If a user tries to enter multiple Email addresses, an error message "Please enter a valid Email address for notification" will be seen. Refer to: KB39168: Receive error "Please enter a valid Email address for notification" when entering multiple Email addresses for delivery notification in MicroStrategy Distribution Services 9.x.
