To Setup Groupware, you need to provide the agent account with full access to all existing mailboxes in Exchange. You will also need to add this access to all new users you create. it will save time to provide that service account access to all existing and future mailboxes. The commandlet in the administration guide does not work correctly, so use the following:
“Get-MailboxDatabase -identity “[mailbox database name]” | Add-ADPermission -user [username] -AccessRights GenericAll”
The account you run this as will need to be a full domain administrator as well.