Compaq Management

Here is the problem:

I?ve got a small network of 25 clients and 3 servers in one NT 4.0 domain. All PCs are Compaqs. I found a program called Compaq Insight Manager that is made for monitoring the network. I?ve installed agents on all PCs and CIMon my machine. When I scan IP range it finds all the PCs on network but then all clients are disappearing and only servers stay. What?s more ? servers are shown as unavailable. What did I do wrong?