There is no way to have PingPlotter running as a service *and* to have it interacting with multiple remote desktop sessions at the same time. You can use the remote desktop switches (as discussed in the previous response), which has been used successfully by many people.
Beyond this, there are a few possibilities, depending on the environment you're using and requirements you have.
* If your people are connecting to a single Windows 2003 server because that's the only way out of your network, then you can set up a remote agent on the server and have them run the local client on their machines. See here for details on this:
http://www.pingplotter.com/manual/pro/remote_trace.html* You can run PingPlotter on a Windows XP "server" somewhere (rather than the 2003 server). The problem here is the user interface of the service can only be surfaced through the console on Windows 2003 - and because XP is always running as the console, you can log in just fine that way.
* If you need to make settings changes, stop the service, run PingPlotter as an application and make changes, then close the application and re-run the service. This will then load all your changes. Then use the web interface to add/remove targets.
Depending on your environment's constraints and requirements, there may be other solutions. If you let us know your needs in more detail, we'll be happy to respond.
- Pete