Reserved Resource Error?

[NT_Engineer]

I have a NIcDAQ-9172 with 5 cards plugged into the chassis.  I have 2 - NI9472 24 V digital output cards, 1 - NI9263 analog output card, 1 - 9215 analog input card, and 1 - 9217 RTD card.

In my program I am sequencing 13 solenoid valves using the 24 V digital output card, reading 3 RTDs, and reading the analog output signal from a CO2 gas analyzer.  The attached program will let me pull in the RTD signal and sequence the valves. However, if I try to create a analog input channel  to read in the CO2 measurement I receive the 50103 Error - Reserved Resource Error.  How can I correct this? I need this signal only to be acquired whenever the Read232 tab is sequenced in the case structure, and these measurements will be written to the valve that is turned on at the time.  For testing purposes, I just have two Write to Measurement File. VIs connected to the RTD signals to make sure that I can append each file only when its corressponding valve is turned on.

Below I have a screen shot of the error, the VI that works, and the VI that I am having trouble with.

[Dennis_Knutson]

This is a very common error and you could have doen a forum search to find the solution. Because the analog inputs (or analog outputs) have a single, shared convert clock, you are only allowed to have a single task for each hardware resource. You would have to combine all of your data acquisition channels into a single task or stop an existing task before starting a new one.