User running B.04.03 on Windows XP, with 7890 GC, was getting a windows error: 'Chemstation Chemmain has encountered a problem and needs to close.' User could still control GC parameters and do a run as long as they didn't close the error message. When the error message is closed, chemstation is closed as well. This error message was not seen in the offline version. User tried uninstalling and reinstalling chemstation. USer purchased Windows 7 PC and installed Chemstation. Still the same error was happening.
It turns out that the serial number in the GC had an empty space after the CN. Had customer input the correct SN after resetting the GC memory. The correct SN was now displayed in the GC. Online mode was able to connect successfully without any error messages.