Cisco works problem

Status: We newly installed the cisco works monitoring tool in our organization.

Problem: Campus manager>topology services> layer2 view>display view:
When i see the network diagram, i see all my devices & links red(inactive), which is wrong i actually can ping and telnet all the devices through command prompt and also through cisco works.

Question: what is the reason for which i m not able to view proper network topology.

Things Tried: I tried by doing the discovery devices and also tried the data collection options, but still the same result.

I would be thankful to the techieez of techrepublic if i get the solution.

Regards

Anwar!