Error 10800 is a timeout error. I would assume, since you are using a digital trigger, that this error is occurring because the digital trigger is not being received before the device times out (the default timeout in the AI Read VI is 5 seconds).
Are you running an example program or are you running an example you built? I would suggest starting with the shipping example entitled "Cont Acq&Graph (buffered) D-Trig.vi." This example is a continuous analog input with a digital trigger (is set up to trigger off of PFI0).
