Creating two channels with two "daqmx create channel.vi"

Hey guys,
I'm perform some piezo measurements and my program has one channel for the input (signal that excites the piezo) and one channel por the output (piezo's response).
Since the amplitude of the piezo's reponse varies a lot, my program adjusts the range of the acquisition changing the "minimum value" and "maximum value" properties in the " daqmx create channel.vi". Such an adjustment makes no sense in the input channel once the excitation has constant amplitude.
That is why I need to use two "create channel.vi". I could create the two channels with a single VI but if I did so, I would not be able to adjust the "maximum/minumum value" of only one of them.
The problem is: Labview always returns the error 50103: The specified resource is reserved.
Below, we have a screenshot of this part.
I tried also to add one "daqmx timing.vi" and one "start task.vi" for each of the "create channel.vi" and synchronize everything via error cluster but it returned the same problem.
The program itself is also attached but I don't think it will be useful.
Please, help me guys!
Regards,
Lucas
Attachments:
two create channels.JPG ‏108 KB
consertando burrada.vi ‏330 KB

Try it like this:
EDIT: OOP, I got the Mins and Maxs reversed.
Using LabVIEW: 7.1.1, 8.5.1 & 2013

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Creating two channels with two "daqmx create channel.vi"

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