Suna,
Error code 33494 primarily occurs when using Dual Channel modules. It indicates that you tried to read from or write to a dual channel module that does not exist. Possible reasons:
1) You are trying to read/write a channel that does not have a module in the FP-TB-10.
2) The Dual Channel module has not been fully inserted and locked into place.
3) The Dual Channel module is damaged in some way such as bent pins.
Regards,
Aaron
LabVIEW Champion, CLA, CPI