what does command status =1 mean

Using an XBEE Pro S2B, I send an AT Command Request (Frame type = 0x17) with an AT command of IS to request IO sample data of enabled analog/digital pins. Assuming all frame data is correct, what would cause a command status in the response of 1 (ERROR)?

I can successfully send %V command and receive a response with the power level.

Thanks.

This is working now. I put an explicit destination address and removed the command option parameter. Not sure which one (or both) was causing the problem.