Go up to see a general description of connection status of Windows Servers.
Check to make sure that you are providing correct authentication credentials. Delete old login and password and retype it. Be sure that you are including the domain (if necessary):
For all Windows Nodes...
Click on the Tools->Options->Monitoring->Windows
For specific Nodes or at the nodes level...
Right click on the Node, select Monitoring-->Windows Performance. Provide domain here similar to DOMAIN\USERNAME. Make sure that Monitor Windows Services is selected. Try to connect with domain name and if that doesn't work, try to connect without a domain name. Temporarily decrease Monitoring time to 1 minute. Wait for a while...
Please also check that you have remote registry service enabled. This is important so that NC can manipulate registry's remotely.
Click on Start --> Run and type perfmon. Try to add counters to the node that you are trying to connect to. NetCrunch uses an API similar to perfmon. So if perfmon connects, so should NetCrunch.
