Acquisizione di due o più canali con DaqExpress collegato ad un NI6009

Please, help me to solve this problem.  I use DAQExpress 5.1 and a NI6009

I need to acquire  multi channels signals ad to produce a simple grafic  visualization  (like a multi track oscilloscope).

I try to configure  two channels, using two separate acquisition task, but when run the application,  I get this error "Error -50103 occurred at Function.gvi"

Is it possible to run two acquisition task at the same time with NI6009?

Is available a file with this features?

Please let me know.

Thanks

Roberto

Please, can you indicate where is possible to find a complete guide to program DAQExpress 5.1 in PDF (not on line short and poor)?