Hello,
Thank you for contacting National Instruments.
Check to make sure that none of the pins on your DAQ card(s), cable(s), cable connector, or modules are bent. Also, make sure that you are not using a SH68-68D1 cable. These cables are designed for use with our digital boards and pins 19, 35, 43 and 56 aren�t connected. This is problematic for the SCXI chassis because pin 19 or DIO 4 for e-series boards is used to control the chassis. A quick test to see if this is your problem is the digital cables are black and the others are grey. You will need to use a SH6868 (grey) cable.
If neither of these suggestions resolves your problem, let me know.
Matthew C
Applications Engineer
National Instruments