The red LED's indicate Open Thermocouple detection. However, each channel can be configured for either thermocouple (temperature) or voltage measurements. If a channel is configured for one of the voltage ranges (+/-25, +/-50, +/-100, -20 to +80 mV), Open Thermocouple does not apply so the LED's are deactivated. Use the NI-FieldPoint software to make sure that your channels are in one of the temperature modes and not in voltage mode.
Regards,
Aaron