HP D2D Manual page 13

NOTE: In some cases, when switching the D2D Backup System from No Authentication or
User Authentication mode to AD mode, it may be necessary to log out and back into a
Windows client before it is possible to access the D2D shares.
9. In order for Data Protector to be able to authenticate with the D2D shares it must run the "Data
Protector Inet" service under the new local user account that has been created on the D2D
Backup System and on the Media server.
Change the logon account via the Services menu in Windows Computer Management. After
changing the login credentials the service must be restarted for it to take effect. In this case a
user Backup is created and is a member of the BackupUsers group.
Configuring AD Authentication Mode 13