Hi Newkirk,
Thanks for the reply. My colleague solved the problem.
Since the cDQA-9188 is an Ethernet Device, I need to "reserve" it first. The steps are as follows:
1. In NI MAX (software on the desktop), select the rack [My System -> Devices and Interfaces -> Network Devices -> NI cDAQ-9188]
2. Select ‘Reserve Chassis’ tab.
This way, the cards within the rack shows up in NI MAX and NI SignalExpress.
Thanks all for helping.