Hi, I want to integrate my 4200-SCS with other tools. I connected 4200-SCS with NI GPIB-USB-HS with my PC and tried control 4200 with the labview driver called KI 4200.vi downloaded from the web. It seems worked by the others. However, I found the labview program can only worked for one time and the SQR light turned green. Then the program can't work. I attached the screens on KXCI and the labview program. Any one could help me to solve the problem ? 
Thanks very much!
Best Regards!
Ertao