Cannot install Backup for Microsoft Office 365

[completecs]

I receive a Power Shell error when trying to install Backup for Microsoft Office 365. Receive "Get-ManagementRoleAssignment not recognized" error.

Thank you,
Jim

[Kostya]

The account used to connect to the Microsoft Office 365 for mailbox data backup should belong to that organization, and it will also need sufficient privileges to archive mail from users' mailboxes.

This account should meet the following requirements:

• Application Impersonation role - to get mail items from user mailboxes.
• View-Only Configuration role - to obtain the necessary organization configuration parameters.
• View-Only Recipients role - to view the list of mailbox recipients (required for job creation).
• Role Management role - to manage and verify role assignments.