Before you use Replver, you need to have the Microsoft Exchange Client installed on the computer where you are planning to run this tool. In addition, the client version of Replver must be compatible with the Microsoft Exchange Server version. You can verify compatibility by creating a profile and connecting to the server(s) with the Microsoft Exchange Client. If the client can successfully connect and open both the private and the public stores, then the two versions are compatible and you are ready to run Replver.
Also, the Windows NT account logged on during execution of Replver needs to have Administration privileges on the Microsoft Exchange Server computer as "service account admin" on all sites the tool will access. To complete its work, the Replver program attempts to log on to the system attendant's mailbox on each server. If you don't have adequate permissions on the system attendant's mailbox, this logon will fail.