Hi Surendra,
First check whether the PCo Management service is running(Give the PCo Management URL in a browser and if it works there that means the service is running) and if not then go to the services of the system where PCo is installed and switch on the service.
2. Check the Proxy configurations in MII at System Properties screen. Try adding the proxy bypass filter like *|*.*
Also you can check this thread which also talks about the same issue.
Regards,
Rohit Negi.