Last evening, I was updating a keygen code found on this thread (the Italian one, written in C) to work with my VNA.
I tried almost all the possible option keys to see which one are valid and which ones are rejected, in order to make the code more useful for the ZVR/ZVC family (it was originally designed for the FSP, as far as i know).
I'm mostly doing this out of curiosity and for the benefit of the community, as I personally don't really need most of the advanced firmware options : for complex tasks with a VNA, I tend to post-process the ".s_p" files .
Some option keys are rejected, but strangely some other are accepted but don't appears to do anything (on the surface)...
Furthermore, at least 2 times, an option key froze the VNA (reboot needed) (doesn't seem to be repeatable).
And then I ran into a SERIOUS PROBLEM (screaming and crying loud!!...

) :
one of the option key, I don't now which one, silently downgraded my ZVR (4 receivers) to a ZVRE (3 receivers).
As my ZVR (+ ZVR-B25 option) and a ZVRE internal cabling is different, I lost even the most basic VNA functionalities.
Where am I so far ?
I' still haven't opened the VNA, nor accessed the HDD.
I noticed that the "options.ini" file size changed.(this file is in a sub-directory of C:\r_s\ )
Also, I found some system log messages saying that "options.ini" file is corrupted .(Maybe it happened some time before this problem, see my previous post).
Any suggestion on how the revert the VNA to it's original ZVR identity ?
I hope the setting resides is a WinNT file, not in an EEPROM on the transputer boards (remember the frozen VNA...).
30 years ago, storing settings in an EEPROM was less common I guess.
Maybe a kind soul could share an "options.ini" file from a working ZVR ?
Even better if it comes from a ZVR with the following hardware options : ZVR-25 (External Measurements) ans ZVR-B21 to B24 (step attenuators).
But I would happily do with any flavour of "options.in"

Thanks in advance...
[ And NO, as I had just received this VNA a few days ago, I hadn't clone the HDD... ]