LeCroy's XStream app is tricky to analyze, as it is a distributed system made out of ~100 dlls that are in fact DCOM OLE services. Therefore, even with IDA, analyzing the call flows requires a lot of actual debugging with plenty of various breakpoints and, of course, luck.
One can get some initial hints by tracing the WinAPI calls, as at some point one of the services will look for the calibration files and try to open them with the system call. I can recommend this tool:
http://www.rohitab.com/apimonitorThere are separate services that communicate with the HW (the PCI card). In WaveRunner 6100A case the serial number (along with other parameters, like back-up calibration constants I guess) is on a TSSOP48 FLASH on the acquisition board, but the options are stored on a 1-Wire EEPROM on the PCI interface card.
The module responsible for options, loading the scope serial number and computing the scope ID seems to be ConfigMgrSvr.dll, an encrypted/packed DLL that also contains the option key generation/verification routines. It calls the scope specific HW access service to get the serial number and the options stored in the 1-Wire EEPROM etc. Then all the other services query the ConfigMgrSvr and ask if this or that option is enabled, which model it runs on. This happens very early in the app startup process. It is also the ConfigMgrSvr module that tells the app that no HW is detected, therefore the message 'Not authorized to run on this system' is displayed (if you install XStream on a PC, without the scope bits).
As a side note, interestingly, there seems to be an option to run the software alone in a "simulation" mode and simulate various LeCroy scopes HW. I still haven't figured it out how to enable that, so one could run the app without the 'Not authorized to run on this system' message.
In a recent Tektronix video on MSO58 design efforts they've boasted that they had to build a SW-simulator, as the hardware was not ready (btw this is common practice in the embedded industry). Funny that LeCroy had this for over a decade I guess (along, among other things, with labelled axes, separate display grids and even Tek's UI looks similar to XStream, menu on top, channel, timebase, trigger buttons on the bottom etc).
To the subject. I didn't look how the app loads the calibration files in detail, as I didn't need that. If you manage to get some info on that area please share it here, as I bet it will be useful for other users of second-hand LeCroys.