With the MSMQ RPC transport you can use MSMQ as a reliable transport for your RPC-based applications.
To use MSMQ as an RPC transport, you must install Windows NT Service Pack 3 on each computer running Windows NT Workstation or Windows NT Server that will send or receive RPC packets over MSMQ. You must install DCOM 95 on each computer running Windows 95 that will send or receive RPC packets over MSMQ.
MSMQ routing servers forwarding MSMQ messages that encapsulate RPC packets need not be running Service Pack 3. However, Microsoft recommends that you install Service Pack 3 on all MSMQ routing servers if you are going to use the MSMQ RPC transport.
MSMQ uses authenticated RPC. Authenticated RPC connections must be validated by a Windows NT Server domain controller. If computers access a domain controller over a slow link, RPC connections will start slowly. If the domain controller is offline, computers cannot read messages (sent using the RPC transport) from queues located on other computers.