>>>I don't have the ID of the message (it has been almost 10 years since I got his code). And I don't care how he created this function (btw, "born" is a poor choice of a word :) ). His function works for me.
>>>
>>>>Here is what I found
>>>>
>>>>https://www.berezniker.com/content/pages/visual-foxpro/vfp-implementation-cipher-encryption
>>>>
>>>>So it does seem to be the same algorithm just in VFP code.
>>
>>BTW, in that page the code is not shown properly for me. It's truncated.
>>
>>I am saying, that the C# implementation is not working for high ASCII values and for us it's critical to make it work for all characters.
>
>Is it possible that you are not encoding the VFP string correctly? Viv's code is using encoding 1252.

I am sending you in private our current VFP code we want to reproduce in C#. I haven't written this code, so it's new for me as well.