I am new to this, so please bear with me. I have an E4407B and I am communicating with it via GPIB. I can successfully save a screen shot as a .gif file to the analyzer. I use the MMEM:DATA? <filename> command to retrieve the gif data from the analyzer to store it on my PC. This command seems to work and the .gif is successfully saved on my PC. The problem is that if I try to issue any other commands to the analyzer after this, I get a "Query Interrupted" command. I have tried everything I can think of to get rid of it. I have tried using a different format on the MMEM:DATA command (using MMEM:DATA <filename>,<definite file length>) this gets me an error -161 complaining about invalid block data (I am not sure if it is # followed by number of digits and size followed by some end of line character or what - I am using C++ by the way). I have also gotten the "Query Unterminated" message when trying to use the MMEM:DATA instead of MMEM:DATA which is why I think I must be using the wrong end of line indicater. One other thing, once I get the "Query Interrupted" error, the commands that I send to the analyzer after that still seem to work. I guess my only concern is that my boss doesn't want to see a bunch of "Query Interrupted" messages on his anlayzers as he then thinks there is something more serious amiss. Can anyone give me some guidance on this?