hi,
make sure the OS type and version are support and the robot is a newer robot IE 7.80
http://support.nimsoft.com/downloads/doc/Platform_Support_Availability_current.pdf
Then check the robot.cfg and make sure the spelling of the hub keys are all correct
should look something like:
domain = howeu01-U181202_domain
hubip = 10.130.220.149
first_probe_port = 48000
hub = PrimaryUIM_Hub
hubrobotname = PrimaryUIM
hubport = 48002
You can set the loglevel = 3 and logsize to 5000 and restart the robot watcher service and check the logs for errors as well.