Dear all, i am now writing a vi to control the HP335b, when i run a simple driver's vi (like getting started.vi) i found that the "ag3325b Configure Standard Waveform.vi" got a error and the error code is Hex:BFFA0010 ag3325b Configure Standard Waveform.vi<ERR>Driver Status: (Hex 0xBFFA0010) Invalid value for parameter or property. what should i do to recover the error? p.s.i am now using LV6.1 with visa3.0 and IVI Compliance Package 2.1 installed. Thanks all~~