Testing Lab as follows:
Exchange 2003 Server - 1.8G Intel Celeron, 768MB RAM, plenty of disk space.
Running in a single Exchange Server,back-end setup for RPC over HTTP. Using SSL and OWA via HTTPS works very well.
Bandwidth is business grade cable, 5M/2M.
I have successfully implemented the rpc over http single, back-end server configuration. My Outlook 2003 client can connect and was validated. However, initially, I could open another user's calendar and send mail but have not been able to do so since the first connection. I get error messages stating that the connection to the Exchange server is unavailable. Outlook must be online or connected to complete this action. Also, I have mail stuck in my outbox now that won't go out when it did before.
Does my server and network bandwidth provide enough "horsepower" to run rpc over http? Also, the only way I was able to connect in the first place was to put my Exchange server in the DMZ of my firewall. I tried opening ports 6000-6004 but this apparently wasn't enough. I couldn't make a connection until I exposed all the ports of the Exchange Server.
My follow-up question is, what ports are needed in order to allow rpc over http to work without exposing the entire system?